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Effect of the feeding system on intramuscular fatty acids and conjugated linoleic acid isomers of beef cattle, with emphasis on their nutritional value and discriminatory ability
Abstract
Thirty two Alentejano purebred bulls were used to investigate the effect of four feeding systems (pasture only, pasture feeding followed by 2 or 4 months of finishing on concentrate, and concentrate only) on meat fatty acid composition (GC-FID), including conjugated linoleic acid (CLA) isomeric distribution (Ag[+]–HPLC–DAD). In addition, meat fatty acids and CLA isomers were used to elucidate the impact of the different feeding regimens on the nutritional value of intramuscular fat and their usefulness as chemical discriminators of meat origin. The diet had a major impact on the fatty acid composition of beef (affected 27 of 36 fatty acids and 10 of 14 CLA isomers), which was independent of the fatty acid concentration. Beef fat from pasture-fed animals had a higher nutritional quality relative to that from concentrate-fed bulls. Finally, meat fatty acid composition was an effective parameter to discriminate between ruminant feeding systems, including different finishing periods on concentrate.
... GFB is an important alternative contributing to food sustainability goals by providing higher amounts of potentially beneficial nutrients [5]. First, GFB contains more omega-3 (n-3) polyunsaturated fatty acids (PUFAs), more conjugated linoleic acid (CLA), less omega-6 (n-6) PUFAs, and less cholesterol-raising saturated fatty acids (SFAs) than conventional grain-finished beef [6][7][8][9]. Second, other health-enhancing phytochemicals (such as polyphenolic compounds) are also thought to be more abundant in GFB compared to grain-finished beef [10]. ...
... Differences in the nutritional profile between grass-and grain-finished beef have been studied extensively [6][7][8][11][12][13][14]. However, these studies mostly focused on a limited number of nutrients, such as fatty acids (FAs), minerals, and vitamins. ...
... Differences in the FA profile of beef from grass and grain finishing systems were widely reported in the literature [6,8,12,61,62]. The absence of significant differences between groups regarding SFAs aligns with what others described [6,61]. While some reported that concentrations of SFAs in GFB are higher than grain-finished beef, this is mainly because FAs were reported as percent of total FAs [7,63]. ...
Citation: Krusinski, L.; Maciel, I.C.F.; van Vliet, S.; Ahsin, M.; Lu, G.; Rowntree, J.E.; Fenton, J.I. Measuring the Phytochemical Richness of Meat: Effects of Grass/Grain Finishing Systems and Grapeseed Extract Supplementation on the Fatty Acid and Phytochemical Content of Beef. Foods 2023, 12, 3547. https:// Abstract: Grass-finished beef (GFB) can provide beneficial bioactive compounds to healthy diets, including omega-3 polyunsaturated fatty acids (n-3 PUFAs), conjugated linoleic acid (CLA), and secondary bioactive compounds, such as phytochemicals. The objective of this study was to compare fatty acids (FAs), micronutrients, and phytochemicals of beef fed a biodiverse pasture (GRASS), a total mixed ration (GRAIN), or a total mixed ration with 5% grapeseed extract (GRAPE). This was a two-year study involving fifty-four Red Angus steers (n = 54). GFB contained higher levels of n-3 PUFAs, vitamin E, iron, zinc, stachydrine, hippuric acid, citric acid, and succinic acid than beef from GRAIN and GRAPE (p < 0.001 for all). No differences were observed in quantified phytochemicals between beef from GRAIN and GRAPE (p > 0.05). Random forest analysis indicated that phytochemical and FA composition of meat can predict cattle diets with a degree of certainty, especially for GFB (5.6% class error). In conclusion, these results indicate that GFB contains higher levels of potentially beneficial bioactive compounds, such as n-3 PUFAs, micronutrients, and phytochemicals, compared to grain-finished beef. Additionally, the n-6:n-3 ratio was the most crucial factor capable of separating beef based on finishing diets.
... Authentication methods to guarantee the grassland origin of beef have received recent research attention. In this context, a number of studies have explored the performance of different analytical tools in beef authentication regarding specific cattle feeding systems, i.e., dietary intakes of grass, grass silage, or concentrate [10][11][12][13][14][15][16]. Stable isotopes, FAs, lipidsoluble vitamins, or volatile compounds have been the analytes used for differentiation purposes. ...
... FA analysis of beef (perirenal fat) showed high differentiation power regarding the dietary background of cattle, i.e., beef from concentrate-and pasture-based feeding regimes, or grass-, partially grass-and concentrate-feeding regimes [10,13,14]. In the present study, a principal component (PC) analysis carried out using the percentages of the major FAs of perirenal fat (those with a percentage > 0.4 on total FAs) as variables ( Figure 1) showed a neat separation between both silage groups (GS) and the straw group (Str-AC). ...
... Animals 2023, 13, 261 ...
Beef derived from grass-fed cattle is a specific quality criterion. The effect of grass silage intake on quality characteristics, i.e., fatty acids, fat-soluble vitamins, and lipid-derived volatile composition of intramuscular and perirenal fat from fattening bull weaners were studied. Visible (VIS) and near-infrared (NIR) spectra were also obtained from perirenal fat. Perirenal fat analysis was performed for feeding differentiation purposes. A total of 22 Tudanca breed 11-month-aged bulls were finished on three different diets: grass silage and a commercial concentrate ad libitum (GS-AC), grass silage ad libitum and the commercial concentrate restricted to half of the intake of the GS-AC group (GS-LC), and barley straw and concentrate ad libitum (Str-AC). Feeding had a significant effect (p < 0.05) on γ-linolenic acid and the ratio n-6/n-3 fatty acids. Furthermore, β-carotene content was greater in beef from silage groups than in the Str-AC group. Feeding also affected the perirenal fat composition. Beef from silage-fed bulls and straw-fed bulls could be differentiated by fatty acid percentages, especially 18:0, t-18:1, and c9-18:1, β-carotene content, b* colour value, and carotenoid colour index. However, the VIS or NIR spectra data showed poor differentiating performance, and the volatile composition did not have appreciable differentiation power.
... Grass-fed beef (GFB) meets the demands of consumers who are concerned about nutrition and the environment (Xue et al., 2010). Compared to grain-fed beef, grass-fed and grass-finished beef contains less total fat, less cholesterol, and less myristic and palmitic acids-saturated fatty acids (SFAs) found to be more deleterious for cholesterol levels (Ponnampalam et al., 2006;Alfaia et al., 2009). GFB contains twice as much CLA and up to 25% more PUFAs compared to conventional beef (Van Elswyk and Mcneill, 2014;Berthelot and Gruffat, 2018;Lenighan et al., 2019;Prache et al., 2020;Butler et al., 2021). ...
... Previous studies mainly agree that grass-feeding or finishing results in higher levels of SFAs (around 45% total FA) compared to grain-finishing (43%) (Duckett et al., 2009;Daley et al., 2010;Van Elswyk and Mcneill, 2014). Nevertheless, it is important to note that grass-finished beef products are leaner than grain-finished products (Alfaia et al., 2009). Grassfinished beef has 1.4 g less SFAs than grain-finished beef per 100 g (Van Elswyk and Mcneill, 2014). ...
... Grassfinished beef has 1.4 g less SFAs than grain-finished beef per 100 g (Van Elswyk and Mcneill, 2014). Furthermore, grass-finished beef contains around 3% more stearic acid (C18:0) compared to grain-finished beef; stearic acid is considered neutral in regard to effects on plasma LDL cholesterol (Leheska et al., 2008;Alfaia et al., 2009;Daley et al., 2010;Van Elswyk and Mcneill, 2014). Concentrations of individual SFA were reported in the literature; unfortunately, not all articles report values using the same units, so it is difficult to compare them directly. ...
As the global population increases, so does meat consumption. This trend is accompanied by concerns regarding the meat industry, and consumers are demanding transparency on the environmental and health effects of the products they are purchasing. Many leading health organizations recommend reducing red meat consumption. Nevertheless, no differentiation is made among red meats and beef. The beef production system is generally ignored despite nutritional differences between grain- and grass-fed beef. Compared to grain-fed beef, grass-fed beef contains a healthier fatty acid profile, including more omega-3 polyunsaturated fatty acids and conjugated linoleic acid, and increased concentrations of phytochemicals desired by health-conscious customers. However, there is a lack of consistency among grass-fed beef in the United States regarding clear product labeling and cattle dietary components. Grass-fed beef labeling confusion has emerged, including misunderstandings between grass-fed and grass-finished beef. Along with this, previous studies observed significant nutritional variation among grass-finished beef from different producers across the country. Cattle diet has the strongest influence on the nutritional composition of beef. Therefore, understanding differences in feeding practices is key to understanding differing nutritional quality of grass-fed beef. Feeding cattle diverse pastures composed of multiple plant species including grasses and legumes managed in a rotational grazing fashion results in higher omega-3 polyunsaturated fatty acids and phytochemical levels in beef compared to feedlots and monocultures. Seasonal differences including changes in temperature, rainfall, grazing practices, and plant growth cycles affect the nutritional composition of feeds and ultimately meat. Additional feeds utilized in grass-fed beef production systems such as conserved forages may reduce or increase health-promoting nutrients in grass-fed beef, while supplements such as grape byproducts and flaxseed may improve its nutritional profile. Further research should measure the effects of individual feedstuff and the finishing period on the nutritional profile on grass-fed beef. A better understanding of these details will be a step toward the standardization of pasture-raised ruminant products, strengthening the relationship between grass-fed beef consumption and human health.
... Conventional beef has been shown to have more (by both concentration and proportion) MUFA than organic and/or grazing-based alternatives [35,39,[116][117][118]. It is however unclear why this difference occurs (potentially to do with the supply of oleic acids from conventional diets and/or the de novo synthesis of OA in the muscle), and there are no known reports associating the higher MUFA in conventional beef on human nutrition and health; further research is required. ...
... Consistently across studies, total PUFA content is higher in grass-fed meat, followed by organic meat [39,114,[117][118][119]. A meta-analysis byŚrednicka-Tober et al. [39] found organic meat to have around 23% more total PUFAs than conventional counterparts. ...
... Many studies show beef from grazing systems have lower n-6:n-3 ratios compared with maize silage [105] and grain-based feeding [39,42,113,117,118,126]. The evidence strongly suggests that the more fresh forage in ruminant feeding, the lower the n-6:n-3 ratio in their diet, contributing to a reduced ratio in the resulting beef. ...
Livestock production is under increasing scrutiny as a component of the food supply chain with a large impact on greenhouse gas emissions. Amidst growing calls to reduce industrial ruminant production, there is room to consider differences in meat quality and nutritional benefits of organic and/or pasture-based management systems. Access to forage, whether fresh or conserved, is a key influencing factor for meat fatty acid profile, and there is increasing evidence that pasture access is particularly beneficial for meat’s nutritional quality. These composition differences ultimately impact nutrient supply to consumers of conventional, organic and grass-fed meat. For this review, predicted fatty acid supply from three consumption scenarios were modelled: i. average UK population National Diet and Nutrition Survey (NDNS) (<128 g/week) red meat consumption, ii. red meat consumption suggested by the UK National Health Service (NHS) (<490 g/week) and iii. red meat consumption suggested by the Eat Lancet Report (<98 g/week). The results indicate average consumers would receive more of the beneficial fatty acids for human health (especially the essential omega-3, alpha-linolenic acid) from pasture-fed beef, produced either organically or conventionally.
... However, in general, linoleic acid (C18:2n6) showed lower contents than those indicated in the literature (9.86-23.7%). The results showed that there were significant differences in eighteen out of twentyseven fatty acids analysed, and the fatty acids that showed a significant effect of the rearing system were almost the same as those found in the scientific literature [28,76]. ...
... The F100 samples presented significantly higher values of C18:3n3 and C20:5n3, while F74 samples showed the highest levels of C22:5 n3 and C20:4 n:6. These results coincide with those found by some authors [28,74,76], who point out that feeding with forage significantly increases C18:3n3 and C20:5n3 but also C20:4n6 acids. The highest level of C22:6 n3 was found for F74 samples; this is in agreement with the results reported by Fruet et al. [28], which do not show a linear increase for any of the n-3 fatty acids with the increase of forage in the diet. ...
... The highest level of C22:6 n3 was found for F74 samples; this is in agreement with the results reported by Fruet et al. [28], which do not show a linear increase for any of the n-3 fatty acids with the increase of forage in the diet. In this study, this linear increase was only observed for C20:5 n3, agreeing with Alfaia et al. [76]. Some authors [28] point out that feeding forage increases not only C18:3 n3 in the diet but also the rumen transit time. ...
This study investigated the influence of the production system (conventional vs. organic), the grass consumption level and the ageing period (7 and 14 days) on beef quality. Three groups of samples from Limousin × Avileña calves were analysed: F100, formed by animals fed 100% on forage; F74, formed by animals fed on an average amount of forage of 74%; and F35, formed by animals fed on straw fodder (35%) and concentrate (65%). The results showed that the higher the grass content, the lower the fat oxidation and the higher the n-3 content, but also the higher the SFA level, the initial Warner-Bratzler shear force (WBSF), and the more residue it leaves on chewing. As for the effect of production system, organic samples showed higher intramuscular fat content and lower moisture and MUFA content. These samples were darker and showed lower values for flavour quality. Among the organic samples, F100 had higher n-3 and CLA content and higher values for colour, hardness, odour and flavour quality. Increased ageing time may improve the sensory characteristics of the meat, especially in the case of the F100 samples. The results pointed out that F100 samples aged at least 14 days showed the best physico-chemical, nutritional and sensory characteristics.
... Al analizar los contenidos de grasa de las tres formulaciones evaluadas se obtuvieron diferencias significativas entre ellas en el orden HC (23,39 %) > HST (20,85 %) > HSSPi (18,32 %), lo cual resulta lógico en función de la composición de las mismas. En el caso de la HSSPi, se obtuvo el menor porcentaje lipídico en concordancia con el menor contenido de grasa, reportado por varios estudios, en las carnes de animales criados en libre pastoreo [13,29,30,31], debido al efecto de la densidad energética de la dieta suministrada y la mayor posibilidad de actividad física que tienen estos animales [32,33]. ...
... Mirístico C14:0 0,90 ± 0,02 a 0,60 ± 0,02 b 0,53 ± 0,03 b Por otra parte, la mayor concentración de mono y poliinsaturados encontrada en la HSSPi con respecto a HST, puede explicarse por el efecto de la carne. En este sentido, son varias las investigaciones que describen el efecto favorecedor de los sistemas silvopastoriles sobre la composición lipídica de la carne, observándose un mayor contenido de ácidos grasos poliinsaturados en comparación con el ganado alimentado con grano [30,32,49,50,51]. ...
El objetivo de esta investigación fue evaluar el efecto del empleo de nuez pecana, fibra de trigo y carne bovina obtenida de toretes engordados bajo un sistema silvopastoril intensivo (SSPi), sobre las propiedades fisicoquímicas, microbiológicas y sensoriales de hamburguesas. Mediante un diseño de mezclas se obtuvo la mejor formulación de la hamburguesa empleando como variables independientes los porcentajes de carne de toretes engordados bajo un sistema tradicional (ST), nuez pecana, fibra de trigo, aditivos y mezcla de vegetales, considerando como variables de respuesta el color, sabor, olor, textura y contenido de grasa. La mejor formulación obtenida del diseño fue replicada empleando carne de vacuno SSPi y se elaboró además una tercera formulación control con carne ST y sustituyendo la nuez y la fibra por grasa bovina. A las formulaciones resultantes se les realizó controles físico–químicos, perfil de ácidos grasos, análisis microbiológicos y evaluación sensorial mediante análisis cuantitativo descriptivo. La mejor formulación sugerida por el diseño estuvo compuesta por 65,7 % de carne ST: 11,1 % de nuez pecana; 1,1 % de fibra de trigo; 6,1 % de aditivos y 16 % de mezcla de vegetales. Las formulaciones elaboradas con adición de nuez y fibras (HST y HSSPi) resultaron significativamente superiores desde el punto de vista físico–químico y sensorial a la hamburguesa control (HC), con menores porcentajes de grasa, mejores propiedades de cocción y mayores contenidos en ácidos grasos poliinsaturados, así como una mejor aceptación sensorial, destacándose significativamente en estos parámetros la formulación elaborada con carne SSPi. Desde el punto de vista microbiológico no se encontraron diferencias significativas y todos los productos resultaron microbiológicamente aceptables cumpliendo con los parámetros establecidos en las normas.
... Purchas et al. [42] compared muscle fatty acid composition of Angus-cross heifers finished on a high-concentrate ration in a feedlot in USA to those of similar body weight finished on pasture in New Zealand and found higher levels of t10-18:1 and lower levels of VA and n-3 PUFA in feedlot-finished heifers. Alfaia et al. [47] also finished bulls on pasture, or with increasing time on a high concentrate diet (2 month, 4 month or completely; 70% concentrate: 30% fibrous cubes) and found concentrate finishing also increased muscle t10-18:1 with a small increase in CLA. However, bulls finished on pasture had a higher n-3 PUFA content, with amounts declining with increasing time on the high concentrate diet [44]. ...
... However, bulls finished on pasture had a higher n-3 PUFA content, with amounts declining with increasing time on the high concentrate diet [44]. When Alfaia et al. [47] finished bulls on pasture, they reached 22.7 mg EPA + DHA100 g of muscle. This is about half the amount needed for a source claim in the European Union. ...
... In the present study, no significant differences in total SFA content were observed between diets and breeds. These findings are in agreement with previous studies reporting no difference in SFA content between grass-fed and grain-fed beef [19,46]. Myristic and palmitic acids have the strongest LDL cholesterol-raising effects compared to other SFAs [47,48]. ...
... Beef from GRASS had a ratio of 1.61:1 while beef from GRAIN had a ratio of 8.36:1. Grass-finishing was expected to raise the n-3 PUFA content of beef, consequently lowering the n-6:n-3 ratio [16,18,46,72,79]. ...
Cattle diet and breed modify the nutritional profile of beef. The objective of this study was to compare the fatty acid (FA) and micronutrient profiles of Red Angus (RA) and RA x Akaushi (AK) crossbreed steers fed either a grass or grain diet. This two-year study randomly assigned steers to the diets using a 2 × 2 factorial experiment. FAs and micronutrients were analyzed. Diet effect was the strongest with grass-finished beef being higher in n-3 polyunsaturated FAs (p < 0.001), conjugated linoleic acid (p < 0.05), vaccenic acid (p < 0.05), iron (p < 0.001), and vitamin E (p < 0.001) compared to grain-finished beef. Breed effects were observed for lauric and myristic acids (p < 0.05), selenium (p < 0.05), and zinc (p < 0.01) with AK containing more of these compounds than RA. Diet × breed effects were non-existent. These results indicate that diet has a stronger influence than breed on modifying the nutritional profile of beef. Because of a more favorable FA and antioxidant profile, consumption of grass-finished beef could benefit human health.
... Plant metabolites such as polyphenol oxidase present in red clover are reported to reduce the activity of plant lipases [45,46], while tannins may reduce lipid biohydrogenation in the rumen, although tannins ability to inhibit biohydrogenation remains controversial [47]. A tannin-containing forage (Sainfoin) was reported to have no effect on ALA biohydrogenation. ...
... Dietary guidelines recommend that the n-6/n-3 PUFA ratio for human diets should be below 5.0 [63], and ratios below 4.0 are purported to have a potential to decrease the risk of coronary diseases and cancer, while ratios of 1.0 or 2.0 may contribute to the prevention of obesity [12]. The n-6/n-3 ratios in this study (1.5-3.5) were all below 5.0 and similar or close to those reported for British cattle (2.0 to 2.3) [64], German Simmental bulls and Holstein steers (1.3) [65] and Alentejano cattle (1.8) [45]. Our findings indicate that backgrounding beef cattle on desmanthus augmented forage and finishing them in the feedlot for a short period (95 days) produces meat with a healthy n-6/n-3 PUFA ratio. ...
Lipid metabolism, carcass characteristics and fatty acid (FA) composition of the Longissimus dorsi (loin eye) muscle were evaluated in tropical crossbred steers backgrounded on Desmanthus spp. (desmanthus) with or without feedlot finishing. It was hypothesized that steers backgrounded on isonitrogenous diets augmented with incremental proportions of desmanthus will produce carcasses with similar characteristics and FA composition. Forty-eight Brahman, Charbray and Droughtmaster crossbred beef steers were backgrounded for 140 days on Rhodes grass (Chloris gayana) hay augmented with 0, 15, 30 or 45 percent desmanthus on dry matter basis. Lucerne (Medicago sativa) hay was added to the 0, 15 and 30 percent desmanthus diets to ensure that they were isonitrogenous with the 45 percent desmanthus diet. After backgrounding, the two heaviest steers in each pen were slaughtered and the rest were finished in the feedlot for 95 days before slaughter. Muscle biopsy samples were taken at the beginning and end of the backgrounding phase. Carcasses were sampled at slaughter for intramuscular fat (IMF) content, fat melting point (FMP) and FA composition analyses. Increasing the proportion of desmanthus in the diet led to a linear increase in docosanoic acid (p = 0.04) and omega-6/omega-3 polyunsaturated FA ratio (n-6/n-3 PUFA; p = 0.01), while docosahexaenoic acid decreased linearly (p = 0.01). Feedlot finishing increased hot carcass weight, subcutaneous fat depth at the P8 site and dressing percentage (p ≤ 0.04). The n-6/n-3 PUFA ratio was within the recommended < 5 for human diets. IMF was within the consumer-preferred ≥ 3% level for palatability. The hypothesis that steers backgrounded on isonitrogenous diets augmented with incremental proportions of desmanthus will produce similar carcass characteristics and FA composition was accepted. These findings indicate that a combination of tropical beef cattle backgrounding on desmanthus augmented forage and short-term feedlot finishing produces healthy and highly palatable meat.
... Several approaches have been examined in this regard . Beef and milk from cattle offered pasture or concentrates have been distinguished based on their fatty acid composition (Alfaia et al., 2009;O'Callaghan et al., 2016). Our second objective was to confirm the potential of using the fatty acid profile to discriminate between grass-and concentrate-finished beef, between different sources of concentrate-finished beef and between beef from different sire breeds. ...
... Methods that validate the elements of a system of production are therefore required. Garcia et al. (2008) and Alfaia et al. (2009) showed that beef from cattle finished on pasture or concentrates could be distinguished (94-100% correct classification after crossvalidation) based on their differences in fatty acid composition. ...
The influence of modifying a traditional 24-mo dairy steer calf to beef production system on the fatty acid composition of the longissimus muscle and its potential to authenticate beef provenance was examined. Fifty-four male calves (n = 18 per sire breed), progeny of Holstein-Friesian cows mated with Holstein-Friesian (HF), Aberdeen Angus (AA) and Belgian Blue (BB) bulls were at pasture from March until August of their second year when they were assigned to a 3 (breed types) × 3 (finishing strategies) factorial experiment. The three finishing strategies were (i) pasture only for a further 94 d prior to slaughter (21 mo of age) (Grass), (ii) concentrates ad libitum indoors for 94 d prior to slaughter (21 mo of age) (EC) and (iii) pasture only for a further 94 d followed by concentrates ad libitum indoors for 98 d prior to slaughter (24 mo of age) (LC). Compared to EC, muscle from Grass had a lower intramuscular fat concentration and omega-6: omega-3 polyunsaturated fatty acid (PUFA) ratio and higher proportion of conjugated linoleic acid. A longer period at pasture pre-concentrate finishing increased the concentration of omega-3 PUFA which was still lower than in Grass. To maximise the omega-3 PUFA concentration, a late-maturing breed is more appropriate while to maximise conjugated linoleic acid, an early-maturing breed is more appropriate and both should be finished on grass. Chemometric analysis confirmed that the fatty acid profile can authenticate "Grass-Finished" beef per se and has potential to distinguish "Concentrate-Finished" beef based on the length of grazing prior to finishing, but not distinguish between sire breeds.
... In every case, the grass-fed beef had a higher OB than the grain-fed beef. Adapted from data provided by (Aldai et al., 2011;Alfaia et al., 2009;Duckett et al., 2013;Garcia et al., 2008;Hiller et al., 2011; Selected studies comparing grass-fed and grain-fed beef Hwang & Joo, 2017;Krusinski, Maciel, Sergin, Goeden, Schweihofer, et al., 2022;Leheska et al., 2008;Najar-Villarreal et al., 2019;Turner et al., 2015). ...
Most beef cattle in the US are feedlot-finished where intensive feeding of grains is used to increase weight and yield; however, a minority are raised in grass-fed operations that use exclusive pasture, rangeland, and hay for feeding, possibly leading to benefits for the land, soil, ecosystems, forages, and the meat itself. These operations use a variety of methods, and the goal of this was to recognize differences in the soil and forage metrics to help understand the resulting meat fatty acid composition and mineral content. We collected these samples from 78 sets of farmers while testing 25 sets of grain-fed controls, usually purchased from a store. We found major differences in organic matter between beef pasture soil and corn field soil and in the fatty acid content of forage and grains. These differences were highlighted with better fatty acid composition and mineral content in grass-fed meat. These results show the variability in beef operations across a range of variables, providing valuable insights into how different feeding practices impact the quality of beef and the environment.
... The proportion of conjugated linoleic acid (CLA) in beef affects its nutritional quality and health benefits [7]. Dietary supplementation with CLA reduces body fat, increases lean muscle mass, decreases atherosclerosis severity, and inhibits carcinogenesis [51][52][53]. We found that only CLA isomers (C9T11, C9C11, T10C12) existed in SC fat but not in LL and SM meat, and the C9T11 and C9C11 levels increased with HCEP diets. ...
The quality and nutritional value of meat are significantly attributed to the composition of fatty acids (FAs). This investigation used gas chromatography to assess FAs in longissimus et lumborum (LL), semimembranosus (SM), and subcutaneous fat (SC) tissues of 18 heifers feeding low (15%, LCEP) or high (30%, HCEP) cassava bioethanol by-products (CEP) and 0 (CPO-0), 2 (CPO-2), or 4% (CPO-4) crude palm oil (CPO). The experimental diet was provided at 1.75% of body weight, along with free access to rice straw and water for 150 days. The results showed that the highest content of saturated (SFAs, 50.14, 42.76, and 68.76%, mainly C16:0), monounsaturated (MUFAs, 44.89, 49.14, and 30.41%, mainly C18:1n9c), and polyunsaturated fatty acids (PUFAs, 4.96, 8.10, and 0.84%, mainly C18:2n6c and C18:2n6t) were observed in LL, SM, and fat tissues. CPO supplementation significantly affected the FAs in LL and SM meat, with CPO-2 and CPO-4 diets leading to decreased SFAs and increased MUFAs and PUFAs compared to the CPO-0 diet. Multivariate analysis showed the most important FAs that highlight discrimination between different oil supplementation levels (CPO-0 vs. CPO-2, CPO-0 vs. CPO-4, CPO-2 vs. CPO-4) in LL (C18:2n6c, C20:3n3, C13:0), SM (C13:0, C18:0, C13:0), and SC fat (C18:2n6t, none, none) tissues. This data generates key insights into FA profiles resulting from different levels of oil supplements in cattle diets, which could influence future research on precision nutrition in beef production.
... Foods lows in (SFA) are preferred by consumers because they are linked to an increased risk of cardiovascular disease and various malignancies [31]. PUSFA consumption should be increased, according to human nutritionists [32]. ...
... The PUFA/SFA ratio is nowadays recommended to be above 0.4 or 0.5 to prevent an excess of SFA, which has a negative effect on the level of plasmatic LDL cholesterol, and an excess of PUFAs, some of which are precursors of clotting agents and are involved in the etiology of some cancers [62]. In addition, the higher contents of total MUFAs found in the meat from the concentrate system is in accordance with other publications [7,46,51,59,63,64] and could be due to the incidence of ingredients in the concentrates, which provide different composition profiles and are of interest for human nutrition. ...
Simple Summary
In Uruguay and some other countries in the region, where pasture grazing has always been predominant in beef production, steers are now increasingly fed grains to shorten the production time. This has implications for meat quality, so meat from both systems (pasture and concentrate) was compared under refrigerated retail conditions in this study. Meat from pasture-fed steers exhibited lower levels of lipid and protein oxidation during the display period, likely due to the higher levels of antioxidants, such as β-carotene and α-tocopherol, found in this investigation. In addition, meat from pasture-raised steers was healthier for consumers in terms of its fatty acid composition and lower intramuscular fat content. In conclusion, meat from pasture-fed steers was more stable during retail refrigeration, possibly allowing for a longer shelf-life, and was healthier for consumers compared to meat from concentrate-fed steers.
Abstract
Beef production in Uruguay is based on pasture (~85%) or concentrate (~15%), resulting in differences in meat quality. The objective of this study was to compare the oxidative stability and color of beef from these two systems during refrigerated retail display. For these purposes, the Semimembranosus muscle was removed from ten Aberdeen Angus steers raised and fed on pasture (130 days prior to slaughter) and from another ten steers fed concentrate (100 days prior to slaughter), sliced. The muscles were placed in a refrigerated showcase for 3, 6, and 9 days. The contents of β-carotene, α-tocopherol, and fatty acids were determined before the meat was placed on display. Lipid and protein oxidation, color, and heme iron content were determined before and during display. The meat from pasture-fed steers had a lower intramuscular fat content (1.78 ± 0.15 vs. 4.52 ± 0.46), lower levels of monounsaturated fatty acids, a lower n-6/n-3 ratio, less lipid and protein oxidation, lower L* and a* values, and higher levels of α-linolenic acid, DHA, total n-3, β-carotene, and α-tocopherol. In conclusion, the meat from pasture-fed steers was more stable during retail display from an oxidative point of view, which may be due to its higher levels of antioxidant compounds such as β-carotene and α-tocopherol and had a healthier fatty acid profile for consumers.
... Regarding fatty acids, the means found for C16:0, C18:0, C18:1c9, total SFA, MUFA, PUFA, C18:1t11 and C18:2c9t11 are consistent with the results described for beef [29,[55][56][57][58][59]. Generally, ruminant meats contain high amounts of SFA, which represent about 50 % of total FA, and are associated with several health disorders [60]. ...
The goal of this research work was to characterize carcass, meat quality traits, proximate composition and lipid profile of cull beef cows reared in extensive systems across various seasons. Mature beef cows (n=65) with mean age of 14.12 years and culled from commercial farms were slaughtered in the Spring, Summer, Autumn and Winter, after a finishing period of about 4 weeks. The meat quality traits were analyzed at 7 d postmortem in Longissimus thoracis, Longissimus lumborum, Semimembranosus, Psoas major and Semitendinosus muscles. The highest carcass yield was obtained in Winter (P <0.05), but the Intramuscular Fat (IMF) means were similar in the different seasons. The meat samples showed high average Warner-Bratzler shear forceWBSF (between 5.41-6.86kg), which may be considered as tough (according to the scale used), except for the Longissimus thoracis which showed intermediate average (5.13kg). However, Psoas major obtained the highest overall acceptance scores. Samples of meat from animals kept in extensive system, natural conditions of Southern Portugal, present high amounts of n-3 PUFA. In Autumn and Summer, portions of 100 g/day of meats with 4.03% and 4.25% of IMF with 1.12 and 2.20% of n-3 PUFA in total fatty acids, can provide between 72.96 and 143.31mg of n-3 PUFA or 31.99 and 61.21mg/d of EPA plus DHA, which corresponds to 12.47% and 24.48% of the requirements recommended by EFSA authorities (250mg/d of EPA plus DHA).
... The PUFA/SFA ratio is nowadays recommended to be above 0.4-0.5 to prevent an excess of SFA, which have a negative effect on the level of plasmatic LDL cholesterol, and an excess of PUFA, which some of them are precursors of clotting agents and are involved in the etiology of some cancers [61]. Besides, total MUFA content was lower in meat from pasture system (P < 0.05) ( Table 2), which is in accordance with other publications [7,46,51,58,62,63]. Furthermore, n-3 content was higher (P < 0.001) and the n-6/n-3 rate was lower (P < 0.05) in meat from pasture ( Table 2), which is desirable because the balance between n-6 and n-3 PUFA is an important determinant in decreasing the risk for cardiovascular diseases and in the prevention of atherosclerosis [64]. ...
Beef meat production in Uruguay is based on pasture or concentrate feeding systems, leading to differences in meat quality. The objective of this study was to compare the oxidative and color stability during refrigerated retail display of beef meat from these two systems. For this, ten Aberdeen Angus steers were reared and fed on pasture and other ten were finished on a concentrate diet. After slaughter, the Semimembranosus muscle was cut into slices and put in a refrigerated showcase for 3, 6, and 9 days simulating commercial conditions. The β-carotene, α-tocopherol, and fatty acid content were determined before the display, and the lipid and protein oxidation, color parameters, and heme iron content were determined before and during the display. Meat from steers fed pasture had a lower content of intramuscular fat, monounsaturated fatty acids, n-6/n-3 ratio, lipid and protein oxidation, L* and a* values, and a higher content of linolenic acid, DHA, total n-3, β-carotene, and α-tocopherol. In conclusion, meat from pasture-fed steers was more stable during the retail display, which can probably be explained by a higher content of antioxidant compounds, such as β-carotene and α-tocopherol, and presented a healthier fatty acid profile.
... Increasing the time on concentrate diets before slaughter led to increased MUFAs and decreased PUFAs proportions in beef (Alfaia et al., 2009;Duckett et al., 1993), whereas increasing time on pastures increased the proportions of PUFAs in beef without affecting MUFAs (Pouzo et al., 2015). ...
... The model obtained enabled a segregation of the four dietary treatments with a correct classification of 93% [9]. Similarly, Alfaia et al. successfully used the FA profile of meat to identify which animals were fed a barley-based concentrate diet in feedlot, those that were pasture-fed, or those that were pasture-fed and subsequently fed a barley-based concentrate [28]. ...
Citation: Smeti, S.; Camin, F.; Bontempo, L.; Tibaoui, S.; Yagoubi, Y.; Pianezze, S.; Piasentier, E.; Ziller, L.; Atti, N. Fatty Acid and Multi-Isotopic Analysis (C, H, N, O) as a Tool to Differentiate and Valorise the Djebel Lamb from the Mountainous Region of Tunisia. Molecules 2023, 28, 1847. Abstract: The objective of this study was to distinguish between the Tunisian Djebel lamb meat and meat from typical Tunisian production systems (PSs) through the fatty acids (FAs) profile and the stable isotope ratio analysis (SIRA). Thirty-five lambs from three different regions and PSs (D = Djebel, B = Bou-Rebiaa, and O = Ouesslatia) were considered for this purpose. The results demonstrated that the PS and the geographic origin strongly influenced the FA profile of lamb meat. It was possible to discriminate between the Djebel lamb meat and the rest of the dataset thanks to the quantification of the conjugated linoleic acids (CLA) and the branched chain FAs. Moreover, statistically different concentrations of saturated, monounsaturated and polyunsaturated FAs and a different n-6/n-3 ratio were found for grazing (D and BR) and indoor (O) lambs, making it possible to discriminate between them. As for the stable isotope ratio analysis, all parameters made it possible to distinguish among the three groups, primarily on the basis of the dietary regimen (δ(13 C) and δ(15 N)) and breeding area (δ(18 O) and δ(2 H)).
... The model obtained enabled a segregation of the four dietary treatments with a correct classification of 93% [9]. Similarly, Alfaia et al. successfully used the FA profile of meat to identify which animals were fed a barley-based concentrate diet in feedlot, those that were pasture-fed, or those that were pasture-fed and subsequently fed a barley-based concentrate [28]. ...
Citation: Smeti, S.; Camin, F.; Bontempo, L.; Tibaoui, S.; Yagoubi, Y.; Pianezze, S.; Piasentier, E.; Ziller, L.; Atti, N. Fatty Acid and Multi-Isotopic Analysis (C, H, N, O) as a Tool to Differentiate and Valorise the Djebel Lamb from the Mountainous Region of Tunisia. Molecules 2023, 28, 1847. Abstract: The objective of this study was to distinguish between the Tunisian Djebel lamb meat and meat from typical Tunisian production systems (PSs) through the fatty acids (FAs) profile and the stable isotope ratio analysis (SIRA). Thirty-five lambs from three different regions and PSs (D = Djebel, B = Bou-Rebiaa, and O = Ouesslatia) were considered for this purpose. The results demonstrated that the PS and the geographic origin strongly influenced the FA profile of lamb meat. It was possible to discriminate between the Djebel lamb meat and the rest of the dataset thanks to the quantification of the conjugated linoleic acids (CLA) and the branched chain FAs. Moreover, statistically different concentrations of saturated, monounsaturated and polyunsaturated FAs and a different n-6/n-3 ratio were found for grazing (D and BR) and indoor (O) lambs, making it possible to discriminate between them. As for the stable isotope ratio analysis, all parameters made it possible to distinguish among the three groups, primarily on the basis of the dietary regimen (δ(13 C) and δ(15 N)) and breeding area (δ(18 O) and δ(2 H)).
... The model obtained enabled a segregation of the four dietary treatments with a correct classification of 93% [9]. Similarly, Alfaia et al. successfully used the FA profile of meat to identify which animals were fed a barley-based concentrate diet in feedlot, those that were pasture-fed, or those that were pasture-fed and subsequently fed a barley-based concentrate [28]. ...
The objective of this study was to distinguish between the Tunisian Djebel lamb meat and meat from typical Tunisian production systems (PSs) through the fatty acids (FAs) profile and the stable isotope ratio analysis (SIRA). Thirty-five lambs from three different regions and PSs (D = Djebel, B = Bou-Rebiaa, and O = Ouesslatia) were considered for this purpose. The results demonstrated that the PS and the geographic origin strongly influenced the FA profile of lamb meat. It was possible to discriminate between the Djebel lamb meat and the rest of the dataset thanks to the quantification of the conjugated linoleic acids (CLA) and the branched chain FAs. Moreover, statistically different concentrations of saturated, monounsaturated and polyunsaturated FAs and a different n-6/n-3 ratio were found for grazing (D and BR) and indoor (O) lambs, making it possible to discriminate between them. As for the stable isotope ratio analysis, all parameters made it possible to distinguish among the three groups, primarily on the basis of the dietary regimen (δ(13C) and δ(15N)) and breeding area (δ(18O) and δ(2H)).
... Approximately 20% to 30% of C18:1n7 absorbed by ruminants is converted into tissues by the enzyme delta-9 desaturase found in the rumen microbiome [27]. The treatment with higher concentrate, on the other hand, may increase the formation of n-6 PUFA precursors in cattle and sheep [28]. This phenomenon, however, was not clearly observed in the loin meat tested here, from either castrated or non-castrated KNBG (p>0.05). ...
Objective:
This study determined the effects of dietary treatments and castration on meat quality, fatty acids (FAs) profiles, and volatile compounds in Korean native black goats (KNBG, Capra hircus coreanae), including the relationship between the population of rumen microbiomes and meat FA profiles.
Methods:
Twenty-four KNBG (48.6 ± 1.4 kg) were randomly allocated to one of four treatments arranged into a 2 × 2 factorial structure. The factors were dietary forage to concentrate ratio (high forage [HF, 80:20] and low forage [LF, 20:80]), and a castration treatment (castration [CA] vs. non-castration [NCA]).
Results:
Among meat quality traits, the CA group exhibited a higher percentage of crude fat and water holding capacity (P < 0.05). The profiles of the saturated fatty acid (SFA) in meat sample derived from CA KNBG showed a significantly lower percentage compared to NCA individuals, due to the lower proportion of C14:0 and C18:0. Feeding a high-forage diet to KNBG increased the formation of C18:1n7, C18:3n3, C20:1n9, C22:4n6 in meat, and polyunsaturated fatty acid (PUFA) profiles (P < 0.05). Consequently, the n6:n3 ratio declined (P < 0.05). There was an interaction between dietary treatment and castration for formation of C20:5n3 (P < 0.05), while C18:1n9, C22:6n3, monounsaturated fatty acid (MUFA) and the MUFA:SFA ratio were influenced by both diet and castration (P < 0.05). Nine volatile compounds were identified and were strongly influenced by both dietary treatments, castration (P < 0.05), and their interaction. In addition, principal component analysis (PCA) revealed distinctly different odor patterns in the NCA goats fed LF diets. Spearman correlation analysis showed a high correlation between rumen bacteria and meat PUFAs.
Conclusion:
These results suggest the essential effects of the rumen microbial population for the synthesis of meat FAs and volatile compounds in KNBG meat, where dietary intake and castration also contribute substantially.
... Compared to conventional grain-finished beef, GFB contains more omega-3 (n-3) fatty acids (FAs) including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), twice as much conjugated linoleic acid (CLA), and 25% more polyunsaturated FAs (PUFAs) [3,[8][9][10][11]. GFB also contains less omega-6 (n-6) PUFAs, less total fat, and less cholesterol-raising saturated FAs (SFAs) [12,13]. GFB has an Samples from grazing areas and supplemental feeds were collected every two weeks. ...
Grass-finished beef (GFB) has demonstrated wide nutritional variations with some GFB having a considerably higher n-6:n-3 ratio compared to grain-finished beef. To better understand these variations, the current study investigated the effects of commonly used supplemental feeds on the nutritional profile of GFB. This two-year study involved 117 steers randomly allocated to one of four diets: (1) grass+hay (G-HAY), (2) grass+baleage (G-BLG), (3) grass+soybean hulls (G-SH), and (4) baleage+soybean hulls in feedlot (BLG-SH). Feed samples were analyzed for their nutritional value, and beef samples underwent analysis for fatty acids (FAs), vitamin E, minerals, lipid oxidation, and shear force. FAs were measured by GC-MS, vitamin E was analyzed chromatographically, minerals were analyzed by ICP-MS, and lipid oxidation was measured via a thiobarbituric acid reactive substances (TBARS) assay. G-SH beef had the highest n-6:n-3 ratio (p < 0.001), while BLG-SH beef contained less vitamin E (p < 0.001) and higher TBARS values (p < 0.001) compared to the other groups. G-HAY beef contained more long-chain n-3 polyunsaturated FAs compared to the other groups (p < 0.001). In conclusion, G-HAY beef had the most beneficial nutritional profile, while soybean hulls increased the n-6:n-3 ratio of beef.
... The FAHFA contents of grilled beef are shown in Fig. 1c, and were lower (p < 0.05) compared to FAHFA in grilled moose meat. The disparity in FAHFA levels between beef and moose meat to beer-based marination and grilling could be due to differences in intramuscular fat composition between beef and moose meat which result from genetics and diets among other factors [35,36]. ...
... Diet plays a crucial role in the genesis, diabetes, and control and treatment of CVD [6]. Among macronutrients, fats have a great impact on chronic diseases such as CVD [7]. Changes in dietary fatty acids can play an important role in prevention and treatment of chronic diseases [8,9]. ...
Background:
Clinical evidences showing the effects of sesame oil on metabolic biomarkers led to inconsistent results.
Propose:
This meta-analysis was designed to examine the effects of sesame oil on metabolic biomarkers in adults, including the maximum number of clinical trials.
Methods:
Google Scholar, PubMed, Web of Science, and Scopus were systematically searched to date up to July 2021 to identify eligible clinical trial studies. We obtained the pooled estimates of weighted mean differences (WMDs) with their 95% confidence intervals (CIs) using random-effects meta-analysis.
Result:
Meta-analysis showed that sesame oil consumption significantly lowered the levels of fasting blood glucose (FBG) (WMD: -3.268 mg/dl; 95% CI: -4.677, -1.86; P < 0.001), and malondialdehyde (MDA) (WMD: -4.847 nmol/dL; 95% CI: -7.051, -2.698; P < 0.001) between the intervention and control groups. Also, this study showed sesame oil consumption significantly decreased HbA1C (WMD: -2.057%; 95% CI: -3.467, -0.646; P = 0.004), systolic blood pressure (SBP) (WMD: -2.679 mmHg; 95% CI: -5.257, -0.101; P < 0.001), diastolic blood pressure (DBP) (WMD: -1.981 mmHg; 95% CI: -3.916, -0.046; P = 0.045), body weight (WMD: -0.346 kg; 95% CI: -0.641, -0.051; P = 0.021), and body mass index (BMI) (WMD: -0.385 kg/m2; 95% CI:-0.721, -0.049; P = 0.025) after intervention. No significant effect was seen in serum insulin levels (p > .05).
Conclusions:
The current study provided some evidence regarding the beneficial effects of sesame oil on metabolic biomarkers. Further studies are still required to confirm our results.
Supplementary information:
The online version contains supplementary material available at 10.1007/s40200-022-00997-2.
... It should be considered that Brachiaria brizantha 'Marandu' pasture contains high concentrations of omega-3 fatty acids (Santana et al. 2017), and that the grass intake is reduced as the level of supplementation increases (Machado et al. 2019). The PUFAs contained or absorbed in fresh grass present higher natural protection against ruminal biohydrogenation; thus, increasing the amount of PUFA that reaches the intestine and consequently increases the percentage of PUFA in the meat (Alfaia et al. 2009). ...
The use of supplements to feed grazing ruminants may improve the productivity and profitability of beef cattle productive systems. This study aimed to evaluate the effect of different supplementation amounts on the meat quality of Nellore steers finished on pasture. A total of 40 steers were maintained on Brachiaria brizantha ‘Marandu’ pasture and finished on different concentrate supplementation amounts: 0%, 0.3%, 0.6%, and 0.9% of body weight (BW). There was no effect (P > 0.10) of supplementation on 14:0, 14:1 n-5, 15:0, 15:1 n-6, 16:1 n-10, 16:1 n-9, 16:1 n-7, 18:1 c-9, 18:1 t-9, 18:2 n-6, conjugated linoleic acid, 20:4 n-6, 22:0 and 22:5 n-3. However, the 17:1 n-10 decreased linearly (P < 0.01), whereas 18:0 increased linearly (P < 0.01) when supplementation was added. There was a quadratic effect (P < 0.10) for 16:0 and 18:1 t-11, as well as for 18:3 n-6. The total concentration of n-3 was linearly reduced, whereas the n-6/n-3 ratio was linearly increased. The use of concentrate supplements for Nellore steers finished on pasture, at amounts up to 0.9% of BW, does not improve the unsaturated fatty acids content. In contrast, the supplementation increases the content of saturated fatty acids in meat of steers.
... Production systems have been shown to alter the composition of beef meat and fat (Alam, Rana, & Akhtaruzzaman, 2017;Alfaia et al., 2009;Noci, French, Monahan, & Moloney, 2007), and consumers who are health conscious are exhibiting a preference for grass fed beef whilst those desiring high marbling are purchasing grain fed products. This results in premium prices being placed upon products according to the production system from which they were derived (Conner & Oppenheim, 2008). ...
A total of 960 beef carcases from northern and southern Australian production regions were assessed by examining the subcutaneous fat. Carcases from four different production systems within each region were assessed, by Raman spectroscopy and the fatty acid composition determined to develop models that best classified the various production systems. As a result, 12 Partial Least Square Discriminant Analysis models were developed. A two-class model based on fatty acid composition was able to correctly classify 99% of grass and grain fed animals. The best Raman spectroscopic model correctly classified 94% of grass vs grain carcases produced in the northern region. For the southern production region, the models had the following classification accuracies; southern long-term grain fed (98%), southern short-term grain fed (95%), southern grass (96%), southern grass supplemented (97%), and the southern model classified grass vs grain (97%). Raman spectroscopy is considered a useful rapid method for classification of beef carcases based upon production system.
... Lipids are composed of fatty acids, which can be oxidized and degraded under certain food processing conditions, resulting in the production of a large number of volatile flavor compounds (Khan et al., 2015;Macleod, 1994). It has been reported that the content of fatty acids in meat is affected by several factors, such as diet, feed system and animal breed (Alfaia et al., 2009;Bautista-Martinez et al., 2020;Lolli, Zanardi, Moloney, & Caligiani, 2020;Warren, Scollan, Nute, Hughes, & Richardson, 2008). Fig. 1 shows the reaction mechanism by which lipid is oxidized to produce meat aroma. ...
Plant-based meat analogues (PBMA) are promising foods to address the global imbalance between the supply and demand for meat products caused by the increasing environmental pressures and growing human population. Given that the flavor of PBMA plays a crucial role in consumer acceptance, imparting meat-like flavor is of great significance. As a natural approach to generate meat-like flavor, the Maillard reaction involving food-derived peptides could contribute to the required flavor compounds, which has promising applications in PBMA formulations. In this review, the precursors of meat-like flavor are summarized followed by a discussion of the reactions and mechanisms responsible for generation of the flavor compounds. The preparation and analysis techniques for food-derived Maillard reacted peptides (MRPs) as well as their taste and aroma properties are discussed. In addition, the MRPs as meat flavor precursors and their potential application in the formulation of PBMA are also discussed. The present review provides a fundamental scientific information useful for the production and application of MRPs as meat flavor precursors in PBMA.
... Polyunsaturated fatty acids support the functionality of the immune system. On the contrary, saturated fats are associated with cardiovascular diseases [45]. In relation to the profile of long chain fatty acids, moringa leaf has a higher abundance of linolenic acid (C18:3) and palmitic acid (C16:0) than stearic acid (C18:0) and oleic (C18:1). ...
... Our results agree with the general finding that an elevated content of C18:3n3 is found in grass-fed beef, since green pastures are a good source of C18:3n3 (Alfaia et al. 2009). Consequently, the precursor of the n-3 series C18:3n3 can be used to synthesise other long-chain (C20-22) n-3 PUFA through an elongation-desaturation pathway (Wood et al. 2008). ...
Context. The increased number of male, dairy origin calves in Ireland due to the abolition of EU milk quotas is a potential resource for the beef industry. Rearing these animals as bulls rather than steers is more efficient from a production perspective. Ensuring satisfactory quality of bull beef from dairy origin is essential. Aim. To determine the effect of two production systems and three muscle types on physico-chemical characteristics and fatty acid (FA) profile of beef from Holstein-Friesian (HF) bulls. Methods. Thirty HF bulls were equally assigned to two production systems: slaughter at under 16 months of age or slaughter at 19 months of age.. Longissimus thoracis (LT), Semitendinosus (ST) and Gluteus medius (GM) muscles were excised post-slaughter for determination of pH, colour, Warner-Bratzler (WB)-variables, cook loss, chemical composition (intramuscular fat (IMF), moisture, protein, ash), collagen characteristics and FA profile. Results. WB-variables and cook loss after 14 days post-mortem ageing, and insoluble and total collagen content were higher while IMF content, redness and saturation at 24 h post-blooming were lower for muscles from the 19-month production system. Muscles from the under 16-month production system had higher saturated fatty acid (SFA) proportion and n-6/n-3 polyunsaturated fatty acid (PUFA) ratio, while muscle from the 19-month production system had higher PUFA proportion, n-3 PUFA proportion and PUFA/SFA ratio. The GM muscle had the lowest L* value, followed by LT and ST. Yellowness, saturation and hue angle were greater in ST. LT had lower WB-variables, cook loss, moisture, and higher IMF content than ST and GM. The PUFA proportion and PUFA/SFA ratio were highest in ST, followed by GM and LT. IMF, total FA, SFA and monounsaturated fatty acid (MUFA) concentrations were higher in LT from the under 16-month production system bulls (the interaction). Conclusions. Beef from the under 16-month production system compared to beef from the 19-month production system, and LT compared to ST and GM muscles had better quality characteristics in terms of lower WB shear force and higher IMF concentration. Implications. Dairy bulls can produce beef of acceptable quality. The findings will guide selection of the combination of production system and muscle type most appropriate to specific market requirements.
... The Palmitic acid concentration in beef cattle in the present study ranges from 19.18 to 11.75. Less value was reported (18.42 mg/g) for grass fed crossbred steers and higher value was reported (26.9 mg/g) for mixed cattle production [42] [43]. Proportion of Stearic acid was similar between breeds except in age categories between 4 and 6 years. ...
... The previous studies reported that bulls could adapt to different feeding strategies without significant effect on meat quality (Manni et al. 2018). Also, Alfaia et al. (2009) considered that a high-forage diet had nutritional advantages for ruminants and conducive for the activity of cellulose-decomposing bacteria, which synthesized intermediate isomers, biohydrogenated intermediate isomers trans11-18:1 (t11-18:1) and cis9, trans11-18:2 (c9, t11-18:2) and n-3 polyunsaturated fatty acid (PUFA) of meat. ...
Carcass parameters, meat quality, fatty acid profile, and amino acid composition of Simmental bulls fed a diet based on various forage silages (VS) compared with the one based on only corn silage (CS) were investigated. A total of thirty male Simmental (440.5 ± 11.5 kg) was selected and assigned randomly divided into two treatments. All animals were fed twice daily (0700 and 1700 h) and water was supplied ad libitum, feed considering 5 to 10% refusals. The period of 207 days fattening trial was divided into three stages as P1 (1 to 64 days), P2 (65 to 130 days), P3 (131 to 207 days). Six beef cattle were slaughtered from each group at the end of the experiment. Substituting CS with VS in the finishing diet did not have a significant effect on slaughter performance, nutrient content, fatty acids, and amino acids profile (P > 0.05). However, the intramuscular fat and connective tissue content of the VS diet was lower compared with the CS diet (P < 0.05). Also, beef cattle fed VS diet could improve eye muscle area, increase histidine content and diameter of muscle fiber. In conclusion, substituting corn silage with various forage silages in the diet of beef cattle could potentially reduce the negative effect under the studied conditions. © 2021 Friends Science Publishers
... It should be considered that Brachiaria brizantha 'Marandu' pasture contains high concentrations of omega-3 fatty acids (Santana et al. 2017), and that the grass intake is reduced as the level of supplementation increases (Machado et al. 2019). The PUFAs contained or absorbed in fresh grass present higher natural protection against ruminal biohydrogenation; thus, increasing the amount of PUFA that reaches the intestine and consequently increases the percentage of PUFA in the meat (Alfaia et al. 2009). ...
The use of supplements to feed grazing ruminants may improve the productivity and profitability of beef cattle productive systems. This study aimed to evaluate the effect of different supplementation amounts on the meat quality of Nellore steers finished on pasture. A total of 40 steers were maintained on Brachiaria brizantha ‘Marandu’ pasture and finished on different concentrate supplementation amounts: 0%, 0.3%, 0.6%, and 0.9% of body weight (BW). There was no effect (P > 0.10) of supplementation on 14:0, 14:1 n-5, 15:0, 15:1 n-6, 16:1 n-10, 16:1 n-9, 16:1 n-7, 18:1 c-9, 18:1 t-9, 18:2 n-6, conjugated linoleic acid, 20:4 n-6, 22:0 and 22:5 n-3. However, the 17:1 n-10 decreased linearly (P < 0.01), whereas 18:0 increased linearly (P < 0.01) when supplementation was added. There was a quadratic effect (P < 0.10) for 16:0 and 18:1 t-11, as well as for 18:3 n-6. The total concentration of n-3 was linearly reduced, whereas the n-6/n-3 ratio was linearly increased. The use of concentrate supplements for Nellore steers finished on pasture, at amounts up to 0.9% of BW, does not improve the unsaturated fatty acids content. In contrast, the supplementation increases the content of saturated fatty acids in meat of steers.
... Diabetics with high blood pressure (BP) are at high risk of CVD (4,5), also abnormal lipid metabolism is common among people with type 2 diabetes, which has significant effects on atherosclerosis and CVD risk (5,6). ...
Objective: A number of studies indicated that olive oil (OO) and canola oil (CO) have lipid-lowering and blood pressure-lowering effects. This clinical trial was done to compare the effects of CO and OO on serum lipids and blood pressure in women with type 2 diabetes. Methods: This randomized controlled clinical trial was done on 77 type 2 diabetic women. 4 weeks before the intervention, lipid-lowering drugs intakes were cut under the supervision of an endocrinologist. The participants were randomly allocated into 2 intervention groups (Balanced diet + 30 grams/day OO or CO) and one control group (Balanced diet + 30 grams/day of sunflower oil (SFO)). Dietary intakes were assessed using three 24-hour food records at baseline and at weeks 4 and 8 of the interventions. At baseline and after 8 weeks, height, weight, waist circumference, systolic blood pressure (SBP), diastolic blood pressure (DBP), serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein (VLDL-C) and high-density lipoprotein cholesterol (HDL-C) were measured and the data were statistically analyzed by SPSS 19. Results: After treatment, SBP (p=0.02), TG (p=0.01) and VLDL-C (p=0.02) were significantly decreased in OO group. None of the variables had significant changes in CO or SFO groups. There were no significant differences in the blood pressure and lipid profile among 3 groups. Conclusion: Although we found no differences between the effects of CO, OO, and SFO, it seems that replacing CO and SFO by OO may have some beneficial effects on SBP, TG and VLDL-C in women with type 2 diabetes.
... The predictor variables follow a similar observation suggesting that a combination of fatty acids derived from ruminal biohydrogenation intermediates and de novo fatty acid synthesis contribute to the discrimination of the feeding provenance of beef. 38 The predictor variables were linearly combined to obtain three canonical discriminant functions (CAN). The first two CAN described 97.1% (CAN 1 = 89.1% and CAN 2 = 8.0%) of the total variance associated with the multivariate structure on the CAN plot ( Fig. 1). ...
BACKGROUND
Concentrate supplementation of a grass silage‐based ration is a typical practice employed for indoor winter finishing of beef cattle in many temperate countries. Plant by‐products, such as dried corn gluten feed (CGF), can be used to replace conventional feedstuffs in a concentrate supplement to enhance the sustainability of ruminant production systems and to improve meat quality. This study examined the chemical composition, fatty acid profile, oxidative stability and sensory attributes of beef (longissimus thoracis muscle) from steers offered grass silage and concentrate supplements containing varying levels (0%, 25%, 50%, 75%) of CGF substituted for barley / soybean meal.
RESULTS
Feeding 50%CGF decreased the protein content and increased intramuscular fat in comparison with 25%CGF. Total phenol content and iron‐reducing antioxidant power followed the order: 0%CGF > 50%CGF and 25%CGF > 0%CGF = 50%CGF, respectively. Compared to 0%CGF, 25%CGF and 75%CGF decreased C14:0 and increased C22:2n‐6, C20:5n‐3 and total n‐3 polyunsaturated fatty acids whereas 75%CGF increased conjugated linoleic acids and C18:3n‐3. Diet did not affect the oxidative stability and sensory attributes of beef patties.
CONCLUSION
The inclusion of up to 75%CGF in a supplementary concentrate for steers increased the proportion of health‐promoting unsaturated fatty acids without negatively influencing the shelf‐life and eating quality of longissimus thoracis muscle. © 2021 Society of Chemical Industry
... Total fatty acids, saturated fatty acids and omega-6/ omega-3 levels have increased. In contrast, Combined Linoleic Acid levels, with anti-cancer properties, have declined (French et al., 2000;Alfaia et al., 2009;Saini and Keum, 2018;Davis et al., 2020). A large proportion of grains in livestock diets has also negative impacts on animal health, leading to excessive use of veterinary medicines (EFSA, 2008). ...
The authors recommended four key measures which will be updated and presented to representatives of the EU institutions on several occasions. The four recommendations are:
1) The phasing out of current subsidies by agricultural area and livestock head, and on energy, large equipment and external inputs. Such subsidies create a strong bias in the productive model at a massive environmental and social cost. The EU should be consistent with its own Green Deal cornerstone: “First do not harm”;
2) If basic subsidies are maintained, they should be paid on a full-time equivalent worker (FTE) basis and not on a hectare (or livestock head) basis anymore;
3) The main part of taxpayer’s money spent within the CAP should be allocated to the production of public goods, i.e. the provision of ecosystem services and the restoration of biodiversity and the ecological network (payment for result-oriented agro-environment and climate measures);
and 4) Although it has been shown that agroecological systems can be more profitable than conventional ones, the transition towards agroecological farming can be difficult and risky for farmers as systems are often more complex. This is the reason why it should be specifically supported by the CAP for several years. This could include specific subsidies, the implementation of a training network with well-trained advisers and a network of innovative farms that could be used as “lighthouses” from which principles may radiate out to local communities.
... These results evidenced that discriminant analysis can be used to explore the relationship between FA composition and the spectra of beef from bulls and their diets. Moreover, earlier works using discriminant analysis gave good results to characterize beef FA profile [36], to distinguish veal of weaned and unweaned calves [37], to separate meat samples according to aging time [38], to differentiate between four different diets to feed cattle during the finishing period [39], or to classify beef samples depending on the finishing diet fed to bulls [40]. ...
The aim of this research was to estimate the fatty acid (FA) content of intramuscular fat from beef by Fourier transform mid-infrared (FT-MIR) spectroscopy. Four diets were supplemented in 10% linseed (LS) and/or 2% conjugated linoleic acid (CLA): CON (without L or CLA), LS, CLA, and LS+CLA. For each diet, 12 young Holstein bulls were allocated. The spectral response of the beef samples was analyzed applying FT-MIR spectroscopy (from 400 to 4000 cm−1) and predictive models were developed using partial least square regression with cross-validation. The obtained coefficients (R2) for some FA, such as α-linolenic acid with a R2 = 0.96 or n-3 polyunsaturated fatty acids (n-3 PUFA) with R2 = 0.93, demonstrate that FT-MIR spectroscopy is a valid technique to estimate the content of FA. In addition, samples were correctly classified according to the animal diet using discriminant analysis in the region 3000–1000 cm−1. The obtained results suggest that the FT-MIR spectroscopy could be a viable technique for routine use in quality control because it provides fast and sustainable analysis of FA content. Furthermore, this technique allows the rapid estimation of the FA composition, specifically n-3 PUFA and CLA, of nutritional interest in meat. It also allows the classification of meat samples by the animal diet.
Beef raised using rotational grazing practices on biodiverse pastures offers potential benefits to animal and environmental health and can improve the nutrient density of meat to favor human health. However, many cattle producers contend with the seasonal unavailability of fresh forage, necessitating the utilization of supplementary feeds or indoor feeding. The objective of this study was to profile secondary metabolites and fatty acids in grass-finished beef supplemented with different feeds (4.5 kg/head/day) and to explore the potential for grass-finished beef authentication. In this two-year study, steers (n = 115) were randomly allocated to one of four diets: 1) pastured/supplemented with hay (control group), 2) pastured/supplemented with baleage, 3) pastured/supplemented with soybean hulls, or 4) baleage/soybean hulls in confinement. Secondary metabolites and fatty acids were measured using UHPLC-MS/MS and GC-MS, respectively. Of the 94 measured metabolites, pyridoxine, alpha-tocopherol, hippuric acid, and gallic acid differed between diets (p < 0.05 for all). Based on random forest classification, beef from the pasture/hay, pasture/baleage, pasture/soybean hulls, and confinement baleage/soybean hulls groups could be identified with a predictive accuracy of 100%, 50%, 41%, and 97%, respectively. Although minimal significant differences were observed, our data indicate that certain supplemental feeds maintain favorable nutritional profiles of grass-finished beef. In addition, metabolomics can predict cattle on exclusively forage-based or feed-based diets with a high degree of certainty.
Beef meat has exceptional nutritional value that distinguishes it from other types of meat and makes it a highly valued food. However, the meat of cattle as well as other ruminants, is characterized by a more complex fatty acid profile compared to the meat of monogastric animals. This complexity is a consequence of the activity of the rumen microflora. In recent decades, changes in animal breeding, feeding practices, and modern slaughtering techniques imparted significant progress in improving beef's nutritional, sensory and market value. Different proportions of concentrated feed and roughages, as well as their types, affect the composition of intramuscular fat. Excluding genetic factors and production practices, nutrition emerges as the main factor influencing the fatty acid profile of beef meat. Today, numerous studies support the nutritional approach to modifying the fatty acid composition of beef meat by using selected feeding stuffs. Therefore, this review aims to collect and systematize data as a guide for implementing such a nutritional strategy in practice, with the health benefits of the final consumers in mind.
Advances in foodomics have demonstrated the feasibility of detecting specific molecules, known as ‘foodomes’, that can serve as biomarkers in fresh meat and dairy products to identify the origin of feeding foods. Identifying these biomarkers is crucial to establish traceability, as consumers demand products of guaranteed quality. In this work, after conducting an exhaustive review of the most relevant scientific documents from the last twenty years, we present a collection of as many as 76 and 66 lipidomes, 42 and 14 metabolomes, 53 and 61 volatile compounds and 8 and 4 isotope ratios (from fresh meat and dairy products, respectively) as potential biomarkers to determine feeding regime in farm ruminants (e.g. fresh herbage, conserved forage or concentrate). CLA9cis-11trans, stearoyl-CoA desaturase, toluene, skatole, and δ13C and δ15N have been widely cited in scientific research to determine the feeding system in ruminants. A combination of these biomarkers with mathematical techniques (discriminant analysis and machine learning) could be used to determine origin and quality in meat and dairy products from ruminants.
Meat is considered a highly nutritious and valued food, although red meat contains high amounts of fat, while goat meat has been established as lean meat. The main objective of this study was to investigate the nutritional quality of meat from Mediterranean kids raised on two forest pastures in the extensive production system (EPS) where goats grazed on a natural forest pasture without concentrate and in the semi-intensive production system (SIPS) where goat received concentrate in addition to pasture grazing. The meat analysis involved 10 kids from each system. The physicochemical characteristics of meat were similar for both management variants of forest raised goats. The meat of the EPS variant contained more (p<0.01) saturated fatty acids (SFA) while that of SIPS more (p<0.01) monounsaturated FA. Contents of polyunsaturated FA (PUFA), PUFA
This study aimed to identify differentially expressed (DE) long non-coding RNAs (lncRNAs) in muscle tissue of Nellore cattle clustered by their fatty acid profile. Longissimus thoracis muscle samples from 48 young bulls were used to quantify fatty acid (FA) (myristic, palmitic, stearic, oleic, linoleic, conjugated linoleic (CLA), α-linolenic and the groups of saturated fatty acids (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), ω3, ω6, PUFA/SFA ratio and ω6/ω3) and to generate RNA-Sequencing data for transcriptomic analyses. The K -means analysis was used to classify the 48 animals into three clusters based on their FA patterns. The C1 had significantly (p ≤ 0.05) higher PUFA, ω3, ω6, linoleic and α-linolenic content than C2 and C3. The proportion of MUFA, CLA and oleic in the C2 and C3 were significantly (p ≤ 0.05) higher in relation to C1, while C3 had significantly (p ≤ 0.05) higher proportions of ω6/ω3, SFA, myristic, palmitic and stearic proportion than C1 and C2. DE analyses were performed on three different comparisons, C1 vs. C2, C1 vs. C3 and C2 vs. C3, and 25, 28 and 22 DE lncRNAs (fold change > | 2 |, p -value < 0.01 and false discovery rate (FDR) < 0.05) were found, respectively. For C1 vs. C2 comparison, a new transcript “ lncRNA_16456.3 ” was found and was interacted with the genes FAM126A (Family with sequence similarity 126 member A) and IL6 (Interleukin-6). These genes were enriched by GO biological function terms related to cellular response to lipid pathway. For the C1 vs. C3 comparison, the lncRNA " lncRNA_13894.1 " interacting with the BNIP3 gene (BCL2/Adenovirus E1B 19 kDa protein-interacting protein 3) was enriched by GO biological function terms related to fat cell differentiation. For the C2 vs. C3 comparison, a new transcript “ lncRNA_16618.6 ” interacted with genes involved in G protein-coupled receptors (GPCRs). Those genes play a crucial role in regulating lipolysis mediated by the cAMP signaling pathway and may be contributing to a higher PUFA fatty acid content in beef. For the three comparisons: C1 vs. C2, C1 vs. C3, and C2 vs. C3, the identified lncRNAs, including genic and intergenic (lincRNA were associated with genes affecting immune response, energy metabolism, lipid and FA metabolism, whose seem to play an essential role in the physiological processes related to meat quality. These findings provide new insights to better understand the biological mechanisms involved in gene regulation of FA composition in beef. This could be valuable for further investigation regarding interaction between lncRNAs and mRNAs and how these interactions may affect meat quality.
The cultured meat industry is continuously evolving due to the collective efforts of cultured meat companies and academics worldwide. Though still technologically limited, recent reports of regulatory approvals for cultured meat companies have initiated the standards-based approach towards cultured meat production. Incidents of deception in the meat industry call for fool-proof authentication methods to ensure consumer safety, product quality, and traceability. The cultured meat industry is not exempt from the threats of food fraud. Meat authentication techniques based on DNA, protein, and metabolite fingerprints of animal meat species needs to be evaluated for their applicability to cultured meat. Technique-based categorization of cultured meat products could ease the identification of appropriate authentication methods. The combination of methods with high sensitivity and specificity is key to increasing the accuracy and precision of meat authentication. The identification of markers (both physical and biochemical) to differentiate conventional meat from cultured meat needs to be established to ensure overall product traceability. The current review briefly discusses some areas in the cultured meat industry that are vulnerable to food fraud. Specifically, it targets the current meat and meat product authentication tests to emphasize the need for ensuring the traceability of cultured meat.
This study developed chicken nuggets with emulsions with different percentages of canola oil (CO) to replace the chicken skin and evaluating the quality of the final product and the effect of frying. The experiment was set up in a 5x5 factorial scheme with the replacement of skin with different percentages of CO (0, 25, 50, 75, and 100%) and storage periods (0, 45, 90, 135,and 180 days), and parameters such as pH and oxidation were evaluated. It was considered a 5x2 factorial scheme (replacement of skin with CO and different sample conditions (raw and fried in CO)) for the analyses of the centesimal composition, fatty acid profile, atherogenic (AI), and thrombogenic (IT) indices. The sensory analysis evaluated the chicken nuggets at time zero. The pH values ranged from 6.62 to 6.86, as an effect of frying, there was an increase in lipid content with increasing levels of substitution (T0-raw: 5.36% and fried: 12.11%; T100-raw: 7.93% and fried: 15.43%) and a decrease in moisture content in relation to the raw sample. There was a decrease in AI (T0%-raw vs. T100%-fried, 0.39 vs. 0.10) and IT (T0%-raw vs. T100%-fried, 0.61 vs. 0.18) with CO addition and frying, and lipid oxidation increased with storage. The ω6/ω3 ratio decreased and the PUFA/SFA increased with the replacement of chicken skin with CO, but there was no difference in the sensory analysis. Even though chicken nuggets are prone to lipid oxidation, it is possible to improve their nutritional value either by adding CO to the meat mixture or by frying them.
Improved understanding and ability to make consistently tender meat have made cooked flavor the determining factor in meat palatability. From the identification of umami flavor to dry-aging strategies, the development of meat flavor is very complex. Stemming from the presence of flavor precursors, and undergoing thermal degradation reactions to create volatile compounds responsible for the aroma and overall flavor of cooked meat. Investigations into precooking strategies, including livestock management and postharvest practices provide insight into development of flavor precursors, nonvolatiles, and muscle tissue as a baseline of what cooked meat flavor could become. Meat cookery methods can also promote flavor differences, including oxidation processes involved in deleterious flavor attributes such as warmed-over flavor.
Additionally, evaluating flavor compounds is essential to connect cooked meat flavor to consumer acceptability. Investigating new, unique methods to quickly classify and quantify flavor compounds act as initial indicators of cooked meat quality, similar to marbling as a measure of palatability. Concurrently, sensory evaluation identifies relationships between flavor compounds and consumer flavor, a benchmark for depicting ideal flavor profiles across various cuts. Subtle changes in product composition and handling strategies could generate drastically different flavor results in cooked meat. As knowledge of flavor development increases, improved flavor outcomes should be possible.
Beef is the main diet component and one of the main sources of protein for humans. The grass-fed beef obtained their nutrients directly from pastures, which contained limited energy
absorption but an abundant amount of fiber. On the contrary, the grain-fed steers received a
grain-based regime that served as an efficient source of high-digestible energy. Rumen may
function differently in the grass-fed and grain-fed regimes. Therefore, grain-fed cattle suffer
stronger metabolic stress than pasture-fed steers; and they tend to easily have metabolic and
infectious diseases. In this study to gain insights into transcriptional regulation in spleen and
rumen tissues under two different regimes include grass and grain, the first high expression
genes in two different conditions were identified by RNA-seq data analyses. Promoter analysis
was performed using a bioinformatics database of Genomatix. Moreover, in this study to the
visualization of regulatory networks containing transcription factors and that regulate the genes
in the rumen and spleen, were used Cytoscape software. Then, promoter analysis leads to the
identification of 31 novel transcription factor activating in the rumen and 10 novel transcription
factors candidates in the spleen in cow fed with grass and grains. Results revealed that 10 genes
with the highest expression were identified in both rumen and spleen. According to the analysis
of the results in the DAVID Database, the processes: reduction of oxidation, regulation of cell
proliferation, ion transport, epididymal development ,and ectoderm development were evaluated
as significant. The results in this study provide valuable insights into molecular mechanisms in
spleen and rumen tissues under two different regimes include grass and grain.
Beef contains functional fatty acids such as conjugated linoleic acid and long-chain fatty acids. This review summarizes results from studies comparing the fatty acid composition of beef from cattle fed either grass or grain-based feed. Since functional lipid components are contributed through dietary consumption of beef, the fatty acid composition is reported on mg/100 g of meat basis rather than on a percentage of total fat basis. Beef from grass-fed contains lesser total fat than that from grain-fed in all breeds of cattle. Reduced total fat content also influences the fatty acid composition of beef. A 100 g beef meat from grass-fed cattle contained 2,773 mg less total saturated fatty acids (SFA) than that from the same amount of grain-fed. Grass-fed also showed a more favorable SFA lipid profile containing less cholesterol-raising fatty acids (C12:0 to C16:0) but contained a lesser amount of cholesterol-lowering C18:0 than grain-fed beef. In terms of essential fatty acids, grass-fed beef showed greater levels of trans-vaccenic acid and long-chain n-3 polyunsaturated fatty acids (PUFA; EPA, DPA, DHA) than grain-fed beef. Grass-fed beef also contains an increased level of total n-3 PUFA which reduced the n-6 to n-3 ratio thus can offer more health benefits than grain-fed. The findings signify that grass-fed beef could exert protective effects against a number of diseases ranging from cancer to cardiovascular disease (CVD) as evidenced by the increased functional omega-3 PUFA and decreased undesirable SFA. Although grain-fed beef showed lesser EPA, DPA, and DHA, consumers should be aware that greater portions of grain-fed beef could also achieve a similar dietary intake of long-chain omega-3 fatty acids. Noteworthy, grain-fed beef contained higher total monounsaturated fatty acid that have beneficial roles in the amelioration of CVD risks than grass-fed beef. In Hanwoo beef, grain-fed showed higher EPA and DHA than grass-fed beef.
A 2-yr study was conducted to evaluate the effects of beef genotypes and feeding systems on performance, carcass traits, meat quality, and sensory attributes. A 2×2 factorial experiment was used to randomly allocate 60 steers in year 1 (YR1) and 44 steers in year 2 (YR2). The two beef genotypes evaluated were Red Angus (RA), and RA x Akaushi (AK) crossbreed. The steers were allotted to two finishing feeding systems: grazing, a multi-species forage mixture (GRASS) and feedlot finishing, conventional total mixed ration (GRAIN). All steers were slaughtered on the same day, at 26 and 18 mo of age (GRASS and GRAIN, respectively), and carcass data were collected 48 h postmortem. Growth and slaughter characteristics were significantly impacted by the finishing system (P < 0.01), with the best results presented by GRAIN. Beef genotype affected dressing percent (P < 0.01), ribeye area (P = 0.04), and marbling score (P = 0.01). The AK steers had a tendency (P = 0.09) for lower total gain; however, carcass quality scores were greater compared to RA. There was a genotype by system interaction for USDA yield grade (P < 0.01), where it was lower in GRASS compared to GRAIN in both genotypes, and no difference was observed between the two genotypes for any GRASS or GRAIN systems. There was no difference in meat quality or sensory attributes (P > 0.10) between the two genotypes, except that steaks from AK tended to be juicier than RA (P = 0.06). Thawing loss and color variables were impacted by the finishing system (P < 0.01). L* (lightness) and hue angle presented greater values while a* (redness), b* (yellowness), and chroma presented lower values in GRAIN compared to GRASS. Sensory attributes were scored better in GRAIN than GRASS beef (P < 0.01). There was a genotype by system interaction for flavor (P = 0.02), where beef from RA had a lower flavor rating in GRASS than in GRAIN, and no difference was observed for AK. Within each system, no difference was observed for flavor between RA and AK. Beef from steers in GRASS had greater (P < 0.01) WBSF than those from GRAIN. These results indicate that steers from GRAIN had superior performance and carcass merit and that AK enhanced these traits to a greater degree compared to RA. Furthermore, the beef finishing system had a marked impact on the steaks’ sensory attributes and consumer acceptability. The favorable results for texture and juiciness in GRAIN, which likely impacted overall acceptability, may be related to high marbling.
Interest in meat fatty acid (FA) composition stems mainly from the need to find ways to produce healthier meat with a suitable ratio of polyunsaturated (PUFA) to saturated fatty acids (SFA) and a favourable balance between n-6 and n-3 PUFA. Studies of grass feeding versus grain feeding cattle have been conducted in different regions throughout the world and suggest that grass-based diets can significantly improve the fatty acid (FA) composition of beef. Compared with grain diets, grass diets contribute to a lower total fat content and more favourable SFA composition i.e. higher proportion of low density lipoprotein (LDL) and cholesterol-neutral stearic acid (C18:0). Feeding fresh grass compared to concentrates results in higher levels of n-3 PUFA in muscle lipids and a more favourable n-6/n-3 PUFA ratio that is within the nutritional recommendations for the human diet.
Context Recent heightened interest of consumers in the origins of their food, together with broader general awareness of environmental matters, has led to an increase in the demand for meat obtained from grazing systems. The importance of local breeds adapted to medium- and low-input production is fully recognised as a means of guaranteeing the sustainability of these farming methods. A finishing system based on pastures and the use of local breeds could both meet the demands of consumers and increase economic returns for Sardinian farmers. Aims The work evaluated the effects of different finishing treatments (pasture PAS-0C vs hay–concentrate-based diets HAY-C) on the quality of meat from young Sarda bulls and the usefulness of meat chemicals as markers to discriminate between finishing systems. Methods Twenty-eight young Sarda bulls were assigned randomly to the following two treatments: finished on natural pasture (PAS-0C group, n = 7), and fed on natural pasture hay ad libitum and concentrate (HAY-C group, n = 21). The latter group comprised three levels characterised by an increasing daily dose of concentrates, as follows: 2.5 kg/animal (HAY-2.5C), 3.3 kg/animal (HAY-3.3C), and ad libitum (HAY-ALC). After slaughter at a fixed age (416 ± 25 days), carcass yield, pH of the Longissimus thoracis (LT) muscle, colour parameters, cooking loss, proximate analysis, α-tocopherol and cholesterol concentration, and fatty acid composition of intramuscular fat of LT were all determined. The discriminating power of the meat chemicals between the two main finishing systems (PAS-0C vs HAY-C) and among the three groups receiving concentrates and hay (HAY-2.5C, HAY-3.3C and HAY-ALC) was assessed using linear discriminant analysis. Key results Pasture-based treatment decreased the intramuscular fat and increased the α-tocopherol concentration of meat and the proportion of some desirable fatty acids (α-linolenic acid and its derivatives eicosapentaenoic acid, docosapentaenoic acid), and improved the value of the ratio of n-6:n-3, without affecting the ultimate pH, colour parameters, and cooking loss. The discriminant procedure was able to discriminate accurately between the two main finishing systems and among the three groups receiving concentrate and hay (P < 0.0001 and P < 0.005 of the Hotelling’s T-squared test respectively). The concentration of α-tocopherol was key to the discrimination of the two main finishing systems, whereas the content of C17:0 and C18:0i were particularly effective in discriminating among the three groups fed with hay concentrate. Conclusions Grazing improves some of the meat traits of young Sarda bulls compared with the effects of a hay-concentrate-based finishing diet. The concentration of α-tocopherol in meat is an effective marker for discriminating the effects of pasture from those of a concentrate-based finishing diet Implications The results highlight the role of pasture-based diet in finishing young Sarda bulls, and could provide a wealth of knowledge for Sardinian beef farmers for delivering meat produce that stands out in the market and meets the demand of consumers more concerned about food origin and its healthiness.
Functional foods are foods that, by virtue of their physiologically active components, provide health benefits beyond basic nutrition. Although the vast number of naturally occurring health-enhancing substances are of plant origin, there are also a number of physiologically active components in animal products that deserve attention for their potential role in health promotion. The aim of this paper was to review the literature for those animal food components that have been linked with human physiological benefits, in order to contribute for the dissemination of this new topic among veterinarians and other animal and food scientists. These components, which potential health benefits and their scientific evidence are described, include: Calcium, probiotics, whey proteins and whey peptides, from dairy products; n-3 fatty acids, from fish; conjugated linoleic acid, from beef and lamb meat; sphingolipids, from eggs; and, the conditionally-essential nutrients L-carnitine, coenzyme Q10, α-lipoic acid, choline and taurine, widely diffused in animal products. In spite of the infancy of functional foods field, increasing evidence supports the observation that functional foods from animal sources may enhance human health.
This paper describes the fatty acid composition, including the isomeric distribution of conjugated linoleic acid (CLA), total lipids and cholesterol in longissimus dorsi (LD) and semitendinosus (ST) muscles of Mertolenga beef from young bulls reared according to Protected Designation of Origin (PDO) specifications. Mertolenga purebred young bulls (n = 30) were raised in a semi-extensive production system, including a finishing period on concentrate feeds for the last 5 or 3 months (October and June samplings, respectively). Mertolenga-PDO beef showed seasonal changes in the levels of some fatty acids (including the predominant 18:2n-6), sums of trans fatty acids and n-3 polyunsaturated fatty acids, some CLA isomers (t11,t13, t11,c13 and t10,c12), sums of geometric groups of CLA isomers and total cholesterol. In addition, significant differences were obtained between LD and ST muscles for most of the analysed parameters. From a nutritional perspective, beef-PDO from June seems to be more healthful than that from October as a consequence of its lower n-6/n-3 ratio. Moreover, the results suggest that the polyunsaturated fatty acid/saturated fatty acid ratio in the ST muscle is consistently above the recommended guideline for human diets, although the values were below that guideline for the LD muscle. Taken together, the data indicate that, although the finishing period of Mertolengo young bulls on concentrate attenuates most of the beneficial grass effects on meat fat throughout the year, beef-PDO from late spring is of greater nutritional value than that from early autumn. Copyright © 2006 Society of Chemical Industry
The objective was to characterize the fatty acid (FA) composition of lamb meat with emphasis on biohydrogenation intermediates (BI) induced by dietary sunflower and linseed oil and to test if a synergistic effect on meat trans-11 18:1 and cis-9,trans-11 18:2 concentrations could be obtained with a blend of both oils. Thirty two lambs were assigned to four groups and fed for 6 weeks one of the following diets: pelleted dehydrated lucerne (Control); and Control supplemented with 7.4% of sunflower oil (SF), linseed oil (LS) or a blend of sunflower and linseed oils (2 : 1 vol/vol) (SFLS). Longissimus thoracis muscles were analyzed for FA. LS increased n-3 PUFA due to contribution of 18:3n-3 but not of very long n-3 PUFA. Total conjugated linoleic acids were similar in oil-supplemented lambs, but the cis-9,trans-11 18:2 was higher with SF than with LS. No synergistic effects on trans-11 18:1 or cis-9,trans-11 18:2 were observed when both oils were fed together. Oil supplementation increased the concentrations of most BI in meat. However, the BI patterns were different for LS and SF. Some FA were only found in lambs fed linseed oil, including the unusual cis-12,cis-15 18:2 which is proposed as a new intermediate of the 18:3n-3 biohydrogenation pathway.
One hundred and eight Merino Branco and crossbred Ile de France×Merino Branco ram lambs were used to evaluate the effects of genotype, feeding system and slaughter weight on fatty acid composition of meat (longissimus thoracis muscle). At 60 days of age, lambs were assigned to the experimental feeding systems: P—pasture with dams; SP—pasture with dams, plus concentrate ad libitum; C—weaning and concentrate ad libitum. Lambs were slaughtered at 24 and 30 kg live weight. The meat had a low fatty acid content. Intramuscular fatty acid (FA) composition was not affected by genotype. Pasture raised lambs (P and SP) showed higher proportion of n-3 FA, conjugated linoleic acid (CLA) and trans-octadecenoic FA, and lower n-6:n-3 ratio, than C lambs. When slaughter weight increased, total FA content increased. Palmitic acid and monoenoic FA increased and polyunsaturated FA decreased with slaughter weight. The CLA proportion increased with slaughter weight, but only for lambs raised on pasture (P and SP). Fatty acid profile was effective in the identification of lamb feeding systems.
The objective of this study was to examine the effects of feeding system and breed on the content of the beneficial n-3 polyunsaturated fatty acids and conjugated linoleic acids (CLA) in beef muscle. German Simmental (GS) (n=31) and German Holstein (GH) (n=33) bulls were produced on either an indoor concentrate system or a grass-based system consisting of a period of summer pasture feeding followed by a winter indoor period on grass silage and a concentrate containing linseed. All animals were slaughtered at 620 kg. The grass-based system increased (P<0.05) the percentage of n-3 fatty acids in the longissimus muscle lipids of bulls (GS 2.22 vs. 0.46%, GH 1.61 vs. 0.34%). The n-6 fatty acid proportions were not affected by the feeding system in GS and GH loin muscle. Therefore, the n-6/n-3 ratio of grass-based GS bulls was 2.0 and of GH was 1.9 in contrast to 8.3 and 6.5 for bulls fed concentrates indoors. The grass-based system increased the percentage of C18:1trans fatty acid isomers in both breeds. The percentage of CLAcis-9,trans-11 (0.87% vs. 0.72% in GS, 0.84% vs. 0.75% in GH) in muscle was significantly higher in animals on the grass-based system.
Dairy fat contains high amounts of saturated fatty acids (FA), which are associated with cardiovascular disease (CVD) risk. Manipulation of dairy cows nutrition allows to decrease the saturated FA content of milk fat, and is associated with increases either in conjugated linoleic acid (CLA) and trans-11-C18:1 contents, or in trans-10-C18:1 content. CLA putatively exhibits beneficial properties on CVD risk, whereas trans FA are suspected to be detrimental. The present study compared the effects of a trans-10-C18:1-rich butter (T10 butter), a trans-11-C18:1+CLA-rich butter (T11-CLA butter) and a standard butter (S butter) on lipid parameters linked to the CVD risk and fatty streaks. Thirty-six White New Zealand rabbits were fed one of the three butters (12% of the diet, plus 0.2% cholesterol) for 6 (experiment 1) or 12 (experiment 2) weeks. Liver lipids, plasma lipids and lipoprotein concentrations (experiments 1 and 2) and aortic lipid deposition (experiment 2) were determined. The T10 butter increased VLDL-cholesterol compared with the two others, and total and LDL-cholesterol compared with the T11-CLA butter ( P < 0.05). The T10 butter also increased non-HDL/HDL ratio and aortic lipid deposition compared with the T11-CLA butter ( P < 0.05). The T11-CLA butter non-significantly reduced aortic lipid deposition compared with the S butter, and decreased HDL-cholesterol and increased liver triacyglycerols compared with the two other butters ( P < 0.05). These results suggest that, compared with the S butter, the T10 butter had detrimental effects on plasma lipid and lipoprotein metabolism in rabbits, whereas the T11-CLA butter was neutral or tended to reduce the aortic lipid deposition.
Conjugated linoleic acid (CLA) consists of a group of geometric and positional isomers of linoleic acid to which anticancerogenic, antidiabetic, and antiatherogenic effects, as well as effects on immune system, bone metabolism, and body composition are attributed. CLA is found predominantly in milk and meat of ruminants due to the importance of rumen micro-organism in the formation of CLA and its precursors. This review attempts to give an overview of the available data on intramuscular CLA concentrations in meat and meat products originating from different animal species. The factors influencing these concentrations are discussed and the estimated human daily intakes as well as the percentage provided by meat are reported.
Meat fatty acid composition is influenced by genetic factors, although to a lower extent than dietary factors. The species is the major source of variation in fatty acid composition with ruminant meats being more saturated as a result of biohydrogenation in the rumen compared to the meat of monogastric animals. The level of fatness also has an effect on the meat fatty acid composition. The contents of saturated (SFA) and monounsaturated (MUFA) fatty acids increase faster with increasing fatness than does the content of PUFA, resulting in a decrease in the relative proportion of PUFA and consequently in the polyunsaturated/saturated fatty acids (P/S) ratio. The dilution of phospholipids with triacylglycerols and the distinct differences in fatty acid composition of these fractions explain the decrease in the P/S ratio with increasing fatness. An exponential model was fitted to the literature data for beef and showed a sharply increasing P/S ratio at low levels of intramuscular fat. Lowering the fat level of beef is thus more efficient in increasing the P/S ratio than dietary interventions. For pork, the intramuscular fat level also affects the P/S ratio, but nutrition will have a larger impact. The fat level also influences the n-6/n-3 PUFA ratio, due to the difference of this ratio in polar and neutral lipids. However, these effects are much smaller than the effects that can be achieved by dietary means. Differences in fatty acid composition between breeds and genotypes can be largely explained by differences in fatness. However, after correction for fat level, breed or genotype differences in the MUFA/SFA ratio and in the longer chain C20 and C22 PUFA metabolism have been reported, reflecting the possible genetic differences in fatty acid metabolism. Breed differences in meat conjugated linoleic acid (CLA) content have not yet been reported, but the c9t11CLA content in meat is positively related to the total fat content. Heritabilities and genetic correlations for the proportion of certain fatty acids have been estimated in a few studies, and correspond to the observations at the phenotypic level in relation to the intramuscular fat level. Although there is potential for genetic change, incorporating fatty acid composition as a goal in classical breeding programs does not seem worthwhile at the present. Enzyme activities have been measured in a few studies, but are not able to explain between-animal variation in fatty acid composition. Biochemical and molecular genetic studies should be encouraged to unravel the mechanisms responsible for differences in the metabolism and incorporation of specific fatty acids in meat. Influence des facteurs génétiques et de l’état d’engraissement sur la composition en acides gras de la viande. Revue. La composition en acides gras de la viande est affectée par divers facteurs : des facteurs nutritionnels, mais aussi des facteurs génétiques, quoiqu’à un degré moindre. L’espèce animale est également une source de variation importante, c’est même la plus importante. La viande des ruminants est plus riche en acides gras saturés que celle des monogastriques, en raison de la biohydrogénation dans le rumen. L’état d’engraissement a aussi un effet très net sur la composition en acides gras. La teneur en acides gras saturés (AGS) et monoinsaturés (AGMI) croît plus rapidement que celle en acides gras polyinsaturés (AGPI) lorsque l’état d’engraissement augmente, ce qui résulte en une diminution de la proportion des AGPI et par conséquent un rapport acides gras polyinsaturés/saturés (P/S) amoindri. Cette baisse du rapport P/S associée à une augmentation du taux de gras intramusculaire peut s’expliquer par la diminution du rapport phospholipides/triglycérides dans les lipides totaux et la composition en acides gras différente de ces deux fractions. Un modèle exponentiel a été adapté aux données de la littérature pour la viande de boeuf et a montré une augmentation nette du rapport P/S lorsque les teneurs en gras intramusculaire sont faibles. La diminution de la teneur en lipides de la viande de boeuf est donc plus efficace pour augmenter le rapport P/S que l’intervention de paramètres nutritionnels. Pour la viande de porc, le taux de gras intramusculaire a également un effet sur le rapport P/S, mais les facteurs nutritionnels auront un effet plus prononcé. Le taux de gras intramusculaire peut aussi influencer le rapport n-6/n-3 AGPI, en raison des différences dans ce rapport entre les phospholipides et les triglycérides. Néanmoins, cet effet est beaucoup moins important que les effets qui peuvent être obtenus avec les paramètres nutritionnels. La mise en évidence de différences dans la composition en acides gras entre les races et les génotypes peut s’expliquer en grande partie par la variabilité de l’état d’engraissement. Cependant, en introduisant un facteur correctif correspondant au dépôt de gras, des différences entre races et génotypes persistent pour le rapport AGMI/AGS et pour le métabolisme des acides gras à chaîne longue (C20 et C22), reflétant de possibles dissemblances génétiques dans le métabolisme des acides gras. Entre races, aucune différence n’a été rapportée, à ce jour, pour la teneur en acides linoléiques conjugués (ACL), mais le taux de l’isomère cis-9 trans-11 dans la viande semble être positivement corrélé à la teneur en gras total. Des études ont estimé les héritabilités et les corrélations génétiques pour les proportions de certains acides gras ; elles correspondent à des observations phénotypiques en relation avec le taux de gras intramusculaire. Bien qu’il existe un potentiel génétique pour modifier la composition en acides gras intramusculaires, l’intégration de la composition en acides gras comme critère dans les programmes de sélections génétiques ne semble pas intéressante actuellement. Quelques études ont mesuré les activités enzymatiques, mais elle n’ont pas permis d’expliquer la variabilité entre animaux dans la composition en acides gras. Des études biochimiques et moléculaires doivent être engagées afin de décrypter les mécanismes responsables des différences dans le métabolisme et l’incorporation d’acides gras spécifiques dans la viande.
Meat has been identified, often wrongly, as a food having a high fat content and an undesirable balance of fatty acids. In fact lean meat is very low in fat (20-50 g/kg), pork and poultry have a favourable balance between polyunsaturated and saturated fatty acids (P:S) and grazing ruminants produce muscle with a desirable n-6:n-3 polyunsaturated fatty acid ratio. In all species, meat fatty acid composition can be changed via the diet, more easily in single-stomached pigs and poultry where the linoleic, alpha-linolenic and long-chain polyunsaturated fatty acid content responds quickly to raised dietary concentrations. Recent work in pigs has attempted to manipulate the n-6:n-3 ratio by feeding higher levels of alpha-linolenic acid (e.g. in rapeseed) or its products eicosapentaenoic acid (20:5) and docosahexaenoic acid (22:6) present in fish oils. In ruminants the challenge is to increase the P:S ratio whilst retaining values for n-6:n-3 found in cattle and sheep fed on forage diets. The saturating effect of the rumen can be overcome by feeding polyunsaturated fatty acids which are protected either chemically, by processing, or naturally e.g. within the seed coat. Some protection occurs when grain-based or grass-based diets are fed normally, leading to relatively more n-6 or n-3 fatty acids respectively. These produce different flavours in cooked meat due to the different oxidative changes occurring during storage and cooking. In pigs and poultry, high n-3 fatty acid concentrations in meat are associated with fishy flavours whose development can be prevented with high dietary (supranutritional) levels of the antioxidant vitamin E. In ruminants, supranutritional vitamin E delays the oxidative change of oxymyoglobin to brown metmyoglobin and may also influence the characteristic flavours of beef and lamb.
The effects of grazed grass, grass silage, or concentrates on fatty acid composition and conjugated linoleic acid (cis-9, trans-11-18:2; CLA) concentrations of i.m. fat of steers fed to achieve similar carcass growth rates were investigated. Fifty steers were divided into 10 blocks based on body weight and assigned at random from within blocks to one of five dietary treatments. The experimental rations offered daily for 85 d preceding slaughter were 1) grass silage for ad libitum intake plus 4 kg of concentrate, 2) 8 kg of concentrate plus 1 kg of hay, 3) 6 kg of grazed grass DM plus 5 kg of concentrate, 4) 12 kg of grazed grass DM plus 2.5 kg concentrate, or 5) 22 kg of grazed grass DM. The concentration of polyunsaturated fatty acids (PUFA) in i.m. fat was higher (P < .05) for steers offered ration 5 than for those given any other ration. Decreasing the proportion of concentrate in the diet, which effectively increased grass intake, caused a linear decrease in the concentration of i.m. saturated fatty acids (SFA) (P < .01) and in the n-6:n-3 PUFA ratio (P < .001) and a linear increase in the PUFA:SFA ratio (P < .01) and the conjugated linoleic acid concentration (P < .001). The data indicate that i.m. fatty acid composition of beef can be improved from a human health perspective by inclusion of grass in the diet.
Ruminant meat is an important source of nutrients and is also of high sensory value. However, the importance and nature of these characteristics depend on ruminant nutrition. The first part of this review is focused on biochemical and dietetic value of this meat. It offers a panel of quantitative and qualitative contributions, especially through its fatty acids characteristics. Since saturated and trans-monounsaturated fatty acids are considered as harmful to human health, their amount in muscles can be reduced by increasing the proportions of dietary polyunsaturated fatty acids (PUFA) absorbed by the animals. On the contrary, some fatty acids (n-6 and n-3 PUFA, conjugated linoleic acid) specifically incorporated in muscle tissues would play a favourable role in the prevention or reduction of major diseases in human (cancers, atherosclerosis, obesity) and therefore be recommended. The second part of this review treats different aspects of the sensorial qualities of meat. Skeletal muscle structure and its biochemical components influence muscle transformation to meat and sensorial qualities including tenderness, colour, flavour and juiciness. This paper shows how nutrition can influence, in ruminants, metabolic activity as well as muscle structure and composition, and thereby affect meat quality.
Vaccenic acid (11-trans octadecenoic acid; VA), a major trans fatty acid in the fat of ruminants, is produced in the rumen and converted in tissues to rumenic acid (9-cis, 11-trans octadecenoic acid; RA), an isomer of conjugated linoleic acid, by Delta(9)-desaturase. There are indications that this conversion also occurs in humans.
The aim of this controlled intervention was to study the conversion of VA to RA in humans after consumption of diets with increasing amounts of VA.
Thirty healthy subjects consumed a baseline diet rich in oleic acid for 2 wk. The subjects were then divided into 3 groups (n = 10 per group) and provided a diet containing 1.5, 3.0, or 4.5 g VA/d for 9 d. All diets contained equal amounts of macronutrients and differed only in their fatty acid compositions. The fats were mixed into conventional foods, and nearly all food was provided during the study.
The proportion of VA in serum total fatty acids increased 94%, 307%, and 620% above baseline with the 1.5-, 3.0-, and 4.5-g diets, respectively. This was associated with a linear increase in the proportion of RA. The conversion rate was 19% on average, with significant interindividual differences with all 3 intakes of VA. The urinary excretion of 8-iso-prostaglandin F(2alpha) increased in all groups (P < 0.001).
The results quantify the desaturation of VA to RA in humans. Conversion is likely to contribute significantly to the amount of RA available to the body, and dietary intakes of VA should thus be taken into account when predicting RA status.
Milkfat is a complex mixture of many diverse FA, some of which have demonstrated health benefits including anticancer properties. Attempts are under way to enrich milkfats with long-chain n-3 PUFA and CLA. It has been recommended that the analysis of these milkfats requires gas chromatography (GC) equipped with long, highly polar capillary columns. However, many analyses have been reported using CARBOWAX type (polyethylene glycol) capillary columns, such as SUPELCOWAX 10, even though the separation characteristics of many of the FA and their isomers present in milkfats have not been described in detail. This includes the isomers of CLA, cis- and trans-octadecenoic acid (18:1), linoleic acid (18:2n-6), and linolenic acid (18:3n-3), and the long-chain PUFA. On the other hand, the resolution of these FA and their isomers has been more fully described using the highly polar capillary columns, such as CP Sil 88 and SP2560 because of the improved resolution obtained using these polar columns. The present study was undertaken to characterize the separation of these FA present in milkfats using a 60-m SUPELCOWAX 10 column, to compare the results to those from a 100-m CP Sil 88 column, and to determine if these two columns could possibly serve to complement each other for the analysis of total milkfat. The advantages of the SUPELCOWAX 10 column were a better resolution of the short-chain saturated from their monounsaturated FA (MUFA) analogs, and a complete separation of the alpha-linolenic (18:3n-3) and eicosadecenoic acid (20:1) isomers. It also provided an alternative elution order of the linoleic (18:2n-6), 18:3n-3 and gamma-linolenic (18:3n-6) acid isomers. On the other hand, the CP Sil 88 column provided a better resolution of the CLA isomers, MUFA, the isolated cis and trans MUFA fractions, the PUFA, and many the 18:2n-6 and 18:3n-3 isomers. A complete analysis of milk lipids using the CP Sil 88 column required the prior separation of total FAME using silver ion-TLC. The results of the present study confirm that the 100-m highly polar capillary GC columns are mandatory for the analysis of milk lipids, and at best, the 60 m SUPELCOWAX 10 capillary column serves as a complementary GC column to provide different separations in certain regions based on its intermediate polarity.
This study examined the effects of feeding pasture vs. concentrate on the distribution of CLA isomers in the lipids of longissimus and semitendinosus muscle, liver and heart muscle, and subcutaneous fat in beef bulls. Sixty-four German Holstein and German Simmental bulls were randomly allocated to either an indoor concentrate system or periods of pasture feeding followed by a finishing period on a concentrate containing linseed to enhance their beef content of n-3 PUFA and CLA. The concentrations of CLA isomers in the different tissues were determined by GC and silver ion HPLC. The diet affected the distribution of individual CLA isomers in the lipids of the different tissues. The concentration (mg/100 g fresh tissue) of the most prominent isomer, cis-9,trans-11 18:2, was increased up to 1.5 times in liver and heart tissue of bulls fed on pasture as compared with concentrate. However, no diet effect was observed for cis-9,trans-11 18:2 in the lipids of longissimus muscle and subcutaneous fat. In all tissues, the second-most abundant CLA isomer in concentrate-fed bulls was trans-7,cis-9 18:2. In contrast, trans-11,cis-13 18:2 was the second-most abundant CLA isomer in all investigated tissue lipids of pasture-fed bulls. The concentration of the trans-11,cis-13 18:2 isomer was up to 15 times higher in tissues of pasture-fed bulls as compared with concentrate-fed animals. Furthermore, diet affected the concentrations of the CLA trans,trans 18:2 isomers. Pasture feeding significantly increased the concentrations of some trans,trans 18:2 isomers as compared with concentrate, predominantly trans-12,trans-14 18:2 and trans-11,trans-13 18:2. Overall, pasture feeding resulted in significantly increased concentrations of the sum of CLA isomers in the lipids of longissimus muscle, subcutaneous fat, heart and liver muscle of German Holstein and German Simmental bulls, but not in semitendinosus muscle.
Muskox (Ovibos moschatus) are ruminant animals native to the far north and little is known about their fatty acid composition. Subcutaneous adipose tissue (backfat) from 16 wild muskox was analyzed and compared to backfat from 16 barley fed beef cattle. Muskox backfat composition differed substantially from beef and the most striking difference was a high content of 18:0 (26.8 vs. 9.77%). This was accompanied by higher levels of most other saturated fatty acids except beef had more 16:0. Muskox backfat also had a lower level of cis-18:1 and this was related to a lower expression of steroyl-CoA desaturase mRNA. Beef backfat had a higher level of total trans-18:1 (4.25 vs. 2.67%). The most prominent trans-18:1 isomers in beef backfat were 10t-18:1 (2.13%) and 11t-18:1 (0.77%) whereas the most prominent isomers in muskox backfat were 11t-18:1 (1.41%), 13t/14t- (0.27%) and 16t-18:1 (0.23%). The total conjugated linoleic acid (CLA) content was higher in beef backfat than muskox (0.67 vs. 0.50%) with 9c,11t-18:2 as the most abundant CLA isomer. The second most abundant CLA isomer in beef backfat was 7t,9c-18:2 (0.10%) whereas in muskox it was 11t13c-18:2 (0.04%). Muskox backfat had a higher content of 18:3n-3 and its elongation and desaturation products 20:5n-3, 22:5n-3 and 22:6n-3 and a lower n-6/n-3 ratio. Overall, the high forage diet of muskox seemed to produce a healthier fatty acid profile and highlighted the need to develop feeding strategies for intensively raising beef that will not negatively impacting fatty acid composition.
Functional foods are foods that, by virtue of their physiologically active components, provide health benefits beyond basic nutrition. Although the vast number of naturally occurring health-enhancing substances are of plant origin, there are also a number of physiologically active components in animal products that deserve attention for their potential role in health promotion. The aim of this paper was to review the literature for those animal food components that have been linked with human physiological benefits, in order to contribute for the dissemination of this new topic among veterinarians and other animal and food scientists. These components, which potential health benefits and their scientific evidence are described, include: calcium, probiotics, whey proteins and whey peptides, from dairy products; n-3 fatty acids, from fish; conjugated linoleic acid, from beef and lamb meat; sphingolipids, from eggs; and, the conditionally-essential nutrients L-carnitine, coenzyme Q(10), alpha-lipoic acid, choline and taurine, widely diffused in animal products. In spite of the infancy of functional foods field, increasing evidence supports the observation that functional foods from animal sources may enhance human health.
The purpose of this study was to characterise and compare the nutritional value of Portuguese Carnalentejana-PDO beef, obtained from Alentejana purebred bullocks reared in a semi-extensive system, with the meat from Alentejana × Charolais crossbred bullocks produced in a conventional intensive concentrate-based system. In addition, seasonal changes in Carnalentejana-PDO beef quality were assessed, by analysing meat samples from animals slaughtered in early autumn and late spring. The results showed that beef-PDO has different intramuscular fat characteristics in comparison with meat from crossbred bullocks fed intensively with concentrate. However, the finishing period of Alentejana purebred bullocks with concentrate seems to attenuate most of the typical grass-fed characteristics of meat fat. Nevertheless, from a human nutrition perspective, Carnalentejana-PDO beef seems to be healthier than that from intensively reared animals since it has a lower n − 6/n − 3 ratio, although always above the recommended guidelines for human diet, and higher proportions of c9,t11 conjugated linoleic acid (CLA) isomer and total CLA relative to saturated fatty acids plus total cholesterol (CLA/SFA + CHR). Furthermore, no seasonal variation in the nutritional quality of beef-PDO was apparent. Taken together, the data indicate that Carnalentejana-PDO beef is of greater nutritional value than intensively produced beef from crossbred bullocks throughout the year.
Food products from ruminants are the major dietary source of conjugated linoleic acids (CLA) for humans. The uniqueness of CLA in ruminant fat relates to the biohydrogenation of dietary unsaturated fatty acids by rumen bacteria. The CLA are inter- mediates in the biohydrogenation, and a portion escape the rumen and are incorporated into milk fat and body fat. In addition, the animal itself synthesizes cis-9, trans-11 CLA from trans-11 octadecenoic acid, another intermediate in ruminal biohydroge- nation that is absorbed. This involves ∆9-desaturase, which is present in mammary tissue (lactation) and adipose tissue (growth). Investigations to alter the content of CLA have typically involved lactating cows (milk fat); fewer data from growing cattle (body fat) are available. Dietary factors that alter the content of CLA because of effects on the rumen biohydrogenation processes in- clude unsaturated fatty acid substrates and altered rumen environment. The cis-9, trans-11 CLA isomer is the major isomer found in ruminant fat; this isomer typically represents 80 to 90% of the total CLA in milk fat, but its proportion in beef fat is less. Under certain dietary conditions the proportion of the trans-10, cis-12 CLA isomer increases. Thus, dietary factors also alter the direction of the biohydrogenation pathways in the rumen. The CLA possess anticarcinogenic effects, which relates to the cis-9, trans-11 CLA isomer, as evident from results with mammary tumors in a rat model. Lipid accretion and nutrient partitioning are also altered by CLA in several species. Recent work demonstrates that this relates primarily to the trans-10, cis-12 CLA isomer, as evident by effects on milk fat synthesis in lactating cows and body fat accretion in growing mice. Overall, consideration of functional foods containing CLA represents an exciting area of potential importance in producing food products derived from ruminants.
We review literature on effects of dietary forages on milk and tissue fatty acid composition of cattle and sheep, with particular emphasis on changes induced by leguminous and biodiverse forages versus intensive ryegrass. Differences are discussed in relation to changes in rumen or duodenal digesta to explain the origin of the differences as, in most cases, increased omega-3 PUFA (i.e., linolenic acid and/or long chain omega-3 PUFA) in milk and intramuscular fat due to feeding of red or white clover and botanically diverse forages could not be attributed to increased dietary supply of linolenic acid (C18:3 n-3). Hence, increased forestomach outflow of C18:3 n-3 has been suggested to originate from reduced rumen lipolysis, with literature providing some evidence for the role of polyphenoloxidase, which is particular active in red clover, to inhibit rumen lipolysis. Increased proportions of CLA c9t11 in milk and intramuscular fat of ruminants fed botanically diverse forages have been associated with increased forestomach outflow of vaccenic acid (C18:1 t11), which is the main precursor of endogenous CLA c9t11 production. Despite the lack of direct evidence, some plant secondary metabolites, present in herbs of botanically diverse forages, are suggested to be potential modifiers of rumen biohydrogenation based on their effects on rumen methanogenesis.
The objective of the experiment with cattle was to produce high quality beef under different feeding conditions and to increase the concentration of essential fatty acids in muscle. In total 10 German Simmental (GS) bulls and 9 German Holstein (GH) steers were kept either on pasture (grass feeding) or in stable (concentrate feeding). Despite biohydrogenation in the rumen, linolenic acid (C18:3n-3) contained in grass was absorbed and deposited into the lipids of muscle. This led to a significantly (p ≤ 0.05) higher content of n-3 fatty acids in the muscle lipids of grazing cattle. The relative amount of total n-3 fatty acids increased from 1.4 g/100 g fatty acid methyl ester (%FAME) in the intensively fed Simmental bulls to 5.5 %FAME in grass fed cattle. The n-6/n-3 ratio of pasture grazing GS bulls was 1.3 in contrast to 13.7 of the animals kept in the byre. The total n-3 fatty acid concentration in beef muscle increased from 24.6 mg (concentrate) to 108.6 mg/100 g wet weight (grazing). In GH steers the total n-3 fatty acid concentration was significantly (p ≤ 0.05) increased up to 86.3 mg/100 g wet weight in pasture grazing steers compared to 28.8 mg/100 g wet weight in animals fed the concentrate. The relative content (%FAME) of CLAcis-9, trans-11 (0.6 vs 0.56 %FAME in GS; 0.55 vs 0.52 %FAME in GH) in muscle was not significantly increased by grazing on pasture in comparison to concentrate feeding neither in GS bulls nor in GH steers, respectively.
Sheep meat is characterized as being high in saturated fatty acids and low in polyunsaturated fatty acids (PUFA), attributes that are regarded as being disadvantageous within the human diet. Despite fresh forage being a particularly rich source of 18: 3n-3 and vegetable oils being high in 18:2n-6 and 18:3n-3, the process of biohydrogenation in the rumen generally results in proportionally less than 0.1 of these essential dietary fatty acids (FA) reaching the small intestine. Increases in muscle content of IS: 3n-3 of 1-2-fold have been achieved by supplementation with oil, or oilseeds, whilst increases of 1-3-fold have been obtained from grazing grass compared with concentrates, but in general the polyunsaturated to saturated FA ratio (P:S) in sheep meat has remained low at approximately 0.2-0.-3. Substantial improvements in the P:S ratio of up to 0.57 and increases ill Muscle and adipose tissue levels of 18:3n-3 of up to 4g/100g FA can be obtained, but rely on protecting dietary PUFA from biohydrogenation. Additionally, increasing tissue supply of 18:3n-3 will result in only a small improvement in muscle concentration of the nutritionally beneficial 20:5n-3 and 22:6n-3, with meaningful increases relying on a dietary supply of these very-long-chain PUFA. An alternative strategy to improve the human health attributes of sheep meat is to decrease tissue levels of 18:0 by increasing the activity of stearoyl-CoA desaturase (SCD), although the response is often relatively small. Despite the apparent negative impact of ruminal metabolism oil muscle FA content, the process of biohydrogenation is often incomplete and several of the intermediaries can have positive effects on human health. Within these intermediaries, future increases in tissue content of cis-9, trans-11 conjugated linoleic acid (CLA) may be obtained by increasing tissue supply directly, although a greater response may be obtained by maximizing tissue supply of trans-11 18: 1 and elevating the action of SCD. Production of a FA profile in sheep meat that is higher in PUFA, particularly the advantageous very-long-chain PUFA, and with flavour and eating characteristics that meet specific market preferences, is a suitable area for research.