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Effect of Condensed Tannins in the Analysis of Dietary Fiber in Carob Pods
Abstract
Insoluble and soluble dietary fiber (IDF and SDF) determined gravimetrically from ripe carob pods after enzymatic treatments, were 32.6% and 6.8%, on dry matter basis. About 50% of the weight of the DF residues corresponded to tannins and protein, because of protease inhibition, and protein-tannin complexes prevented the removal of these constituents in carobs. Nonstarch polysaccharides (14.7% dry weight) and composition were determined by GLC analysis in acid hydroly-sates of samples. The results were discussed showing that the content of DF obtained by enzymatic procedures, including the suggested AOAC method, may be overestimated because of the presence of condensed tannins.
... 2 . 1 .3) (Saura-Calixto, 1988 ;Goiii et al. 1989;Saura-Calixto et al. 1991). Nevertheless, the increase in the excretion of faecal nitrogen may also be due to the stimulation of endogenous N production by the polyphenolic compounds (Butler, 1989 ;Shahkhalili et al. 1990). ...
... 1979) or when it is derived from different sources (Cummings et al. 1976;Calloway & Kretsch, 1978;Kelsay et al. 1978;Anonymous, 1984). Several suggestions have been made to explain the manner in which fibre brings about this effect: (1) the protein of fibre itself is undigested and excreted in faeces (Saunders & Betschart, 1980); (2) the dietary protein is not completely absorbed because of the increased colonic volume due to the addition of fibre (Bender et al. 1979); (3) the fibre decreases the activity of proteolytic enzymes such as trypsin (EC 3 .4.21.4) and chymotrypsin (EC 3.4.21.1) Schneeman, 1978;Stephen, 1987). ...
... 1988) point out a significant increase in faecal N excretion as a consequence of the interaction between polyphenols and dietary protein. Our results (Table 5) show that a large amount of the ingested polyphenols are excreted in faeces, agreeing with in vitro experiments (Saura-Calixto, 1988;Gorii ~?t ul. 1989;Saura-Calixto et al. 1990, 1991 which show that, after treatment with digestive enzymes (a-amylase, protease and amyloglucosidase), a residue containing both polyphenols and proteins remains as the result of the formation of indigestible tannin-protein complexes (Aw & Sawson, 1985;Barroga et al. 1985) and of enzymic inhibition phenomena (Griffiths & Moseley, 1980). ...
The present study was undertaken to explore the effect of apple pulp on weight and composition of faeces. This material is rich in dietary fibre (DF; 620 g dry matter/kg) and contains appreciable amounts of polyphenols. Recent reports indicate that both condensed tannins (CT) and soluble polyphenols form cross-links with protein and inhibit digestive enzymes, affecting the protein digestibility, and may produce a stimulation of endogenous nitrogen excretion. Two groups of male Wistar rats were fed on either a control diet free of DF or a diet containing 100 g apple pulp DF/kg during 7 d after a 4 d adaptation period. Body-weight and food intake were monitored daily and faeces and urine were collected once daily. DF, water content and polyphenolic compounds were measured in faeces, and N content in both faeces and urine. Faecal weight increased in the fibre group by 280 and 240% when compared with wet and dry faecal weights of animals fed on the fibre-free diet. Soluble dietary fibre (SDF) excreted in faeces was 10.9% of the SDF ingested, which suggested a low resistance to fermentation of this fraction. Of the insoluble DF, 43% of the ingested fibre was fermented. Polyphenols were degraded in the intestinal tract. Of the ingested CT, 68.6% was recovered in faeces, while the soluble polyphenols were extensively degraded (85.7% of that ingested). On the other hand, a higher faecal N excretion was observed for the fibre-fed group, suggesting a decrease in the digestibility of the dietary protein and lower apparent digestibility of the dietary protein and lower apparent digestibility and N balance indices.
... According to Owen (2003), flavones content in carob is about 0.132 g/kg) [42], Würsch (1984) and Saura-Calixto (1988) reported a tannin content of 16-20% on dry weight in pods [47,50]. Kamal K. et al. (2013), reported that coumarins content in carob flour is about 4,49ppm while lignins are about 33.06 ppm [51]. ...
... Carob fruit is relatively caloric sice 100 g of caroub flour give about 222 kcal/933 kJ [51]. ...
... CF is unique in its composition due to the presence of high amounts of polyphenols. Most importantly, about 50% of the weight of the carob dietary fiber corresponds to polyphenols (Saura-Calixto, 1988). Carob fiber can be used as a functional food ingredient in a range of food products such as baked goods, extruded products, dairy drinks, health bars, and dietary supplements (Nasar-Abbas et al., 2016). ...
... All samples contained phenolic compounds, however, their content was significantly higher for samples obtained after simulated digestion. CF is a very good source of polyphenols, mainly tannins (Saura-Calixto, 1988). The enrichment of pasta with CF caused an increase in TPC in pasta samples from 3.21 mg GAE/g dry mass (DM) to 4.8 mg GAE/g DM. ...
The aim of this study was to evaluate the effect of carob fiber on pasta properties. Common wheat flour was substituted with 0, 1, 2, 3, 4, and 5 g/100 g of carob fiber. Pasta properties including firmness, color, cooking time, sensory analysis, and antioxidant properties were evaluated. The results showed that carob fiber slightly increased the weight increase index and decreased the optimum cooking time. The lightness of pasta strongly decreased with the proportion of carob fiber, from 61.7 to 26.5 and from 55.8 to 38.6 for uncooked and cooked samples, respectively, whereas the total color difference changed from 24.4 to 38.6 and from 9.6 to 17.2, respectively. A linear decrease in pasta cutting force was observed as the proportion of carob fiber increased. The sensory evaluation of pasta showed that the additive decreased scores for pasta smell but increased scores for color evaluation. Carob fiber up to 4 g/100 g of wheat flour had little effect on pasta's overall acceptability and significantly increased total phenolics content and antioxidant activity of samples. Digestion in vitro caused an increase in total phenolics content and antioxidant activity.
... The milled flour is often added to hot or cold milk for drinking (Morton 1987). The pod consists mainly of pulp (90%), which is rich in sugars (48-72%), but also may contain a large amount of condensed tannin (16-20%) (Würsch et al. 1984;Morton 1987;Saura-Calixto 1988;Bravo et al. 1994;Batlle and Tous 1997). Lower tannin values have been reported in some cases ( Yousif and Alghzawi 2000). ...
... As found here, sucrose was the predominant sugar and fructose was present at relatively low concentrations in pods of Anatolian carob tree. Generally, however, levels of sucrose, glucose and fructose in carob pod reported in the literature showed geographical variation (Würsch et al. 1984;Saura-Calixto 1988;Avallone et al. 1997). ...
Carob pod is the fruit of the carob tree (Ceratonia siliqua L. Fabaceae). The fruit and its products, sold both in large stores and local markets, contribute strongly to the diet of people living in the Mediterranean areas of Europe and Turkey. This study reports the composition of carob pods sampled in West and South Anatolia. Sucrose (437.3 mg/g dry weight), glucose (395.8 mg/g dry weight) and fructose (42.3 mg/g dry weight) were the major sugars identified and quantified in the fruit. Total phenolics (13.51 mg gallic acid equivalents [GAE]/g dry weight), proanthocyanidin (0.36 mg GAE/g dry weight), gallotannins (0.41 catechin equivalents [CE]/g dry weight) and flavanols (3.21 mg CE/g dry weight protein) content of the fruit were also determined. Gallic acid (3.27 mg/g dry weight) was the most abundant phenolic acid present in all three phenolic fractions (free, ester and glycoside) isolated from pods. Aspartic acid (18.25 mg/g dry weight protein) was the predominant amino acid in the pod protein fraction. Eight minerals were quantified in the fruit. Among the analyzed major minerals, K (9.70 mg/g dry weight) was the most abundant element present, and the pods were richer in Ca than in P and Mg. Levels of trace minerals were comparable to other plant species. The data are discussed in terms of the nutritional value of the carob pod.PRACTICAL APPLICATIONThe use of carob fruit and its food products in Turkey has been increasing in recent years. However, knowledge about the composition of carob fruit pod produced in Turkey as well as in Mediterranean countries is lacking. The present work describes a composition scale and the advantages to food technologists and consumers who use the fruit and its fruit products in their diets. The results of the study can also aid in the assessment of adequate compositional information for further studies.
... Fructose (0.54-1.4%) was identified as the lowest amount of sugars in the carob genotypes. Sugar content of carob can be changed based on the geographical diversity (Würsch et al., 1984;Saura-Calixto, 1988;Avallone et al., 1997). In another study reported by Karkacier and Artik (1995), the authors implied that when the fruits are ripe enough to be harvested, it has 91-92% total dry matter and 62-67% total soluble solids, which consists of 34-42% sucrose, 10-12% fructose and 7-10% glucose. ...
... Major essential minerals, i.e. sodium (Na), calcium (Ca), potassium (K), and magnesium (Mg), and trace elements, such as manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), selenium (Se), and molybdenum (Mo), are important to body homeostasis (Otten et al. 2006, Martins et al. 2017. These minerals can bind to the ber in different proportions, mainly bound to inorganic salts such as phytates (Toma and Curtis 1986, Guillén et al. 1987, Southgate 1987, Saura-Calixto 1988, van Soest and Jones 1988, Siddiqui 1989, Martins et al. 2017. Phytates are well known for their Fig. ...
Food components such as phenolics, minerals, proteins and lipids, are associated to dietary fiber (DF), thus limiting their bioavailability. It is estimated that about 50% of the ingested phenolics are associated to DF, due to interactions with hydrophobic aromatic rings and hydrophilic hydroxyl groups of phenolics. Likewise, major essential minerals and trace elements can bind to inorganic salts found in the DF, such as phytates. Proteins can be found naturally linked to DF, particularly to polysaccharides in the cell walls of plants. Furthermore, lipids with a complex chemical structure may also be linked to DF. The main compounds under this category are cutin, suberin, and plant waxes. In this chapter, the chemical interactions between phenolics, minerals, proteins and lipids with DF, their metabolism and absorption, as well as the effect of food processing on their bioavailability are described.
... Also, carob pod is characterized by higher content of dietary fibers (30-40%) and they consist of cellulose, hemicellulose, lignin and galactomannans (Haber, 2002). Furthermore, composition of carob pod is unique due to presence of high amounts of polyphenols (Saura-Calixto, 1988). So far, 24 individual polyphenolic compounds were identified in carob (Owen et al., 2003). ...
In many countries, production of gingerbreads has a long tradition. Gingerbread is a sweet bakery product that can take form of a cake or softer cookie. The formula for gingerbread dough may vary depending on local customs. Generally, it comprises wheat flour, honey, sugar, condiments and chemical leavens. In order to investigate the possibility of using carob flour and sugar beet fibers in formulation of improved gingerbread type biscuits, supplementation of part of the wheat flour with mentioned functional materials was carried out. Experiments were planed according to factorial plan 3 2 , independent variables being carob flour and sugar beet fibers in amounts of 10%, 20% and 3%, 6%, respectively. Quality of utilized gingerbread type biscuits was evaluated through examination of total polyphenolic content, antioxidant activity, pH and sensory parameters. Moreover, microbiological quality of products was determined by mesophilic bacteria, yeasts and fungi count after 2 months of storage. Obtained results showed that the increase of carob flour in biscuits formulation increases antioxidant activity as well as polyphenolic content, while the introduction of sugar beet fibres does not significantly affect parameters mentioned. Sensory analysis showed increased firmness and unpleasant aftertaste in samples with high share of sugar beet fibers. On the other hand, addition of carob flour positively affected colour, aroma and sweetness of biscuits. In terms of overall acceptability, sample with 20% of carob flour obtained the highest score (higher than control sample). Lastly, fortification of gingerbread type biscuits did not affect the microbiological parameters.
... El Kahkahi et al [27] , reports that the content of hydrolysable tannins in the pulp, seed Meknes (P3), pulp Khémisset (P4) and pulp Marrakech (P7) is the highest rate with 7 mg/100 g followed pulps Marrakech (P5) and pulp Fez (P2) with a rate of 6 mg/100 g pulp. Our results are similar than those of Saura Calixto [36] with 1.3% and lower than those of Avallone et al [5] with 95 mg/100 g represented by ellagitannins and gallotannins. Phenolic compounds are known as powerful antioxidants. ...
... It is mainly insoluble, comprising ~ 30-40% of carob pulp and consists of cellulose, hemicellulose, lignin and galactomannans [124]. The uniqueness of carob dietary fiber, that differentiates it from other dietary fibers, lies on the presence of high amounts of polyphenols and also proteins and minerals [124,125]. Furthermore, the galactomannan fraction is of great significance, since their extraction leads to the production of locust bean gum (LBG). Galactomannan is a linear, high molecular weight polysaccharide, consisting of β-(1-4)-mannose backbone with a single d-galactopyranosyl units attached via α-(1-6) linkages as side branch [28,126]. ...
Cocoa originates from the beans of the cocoa tree (Theobroma cacao L.). It is an important commodity and the main ingredient in chocolate manufacture. Its value and quality are related to complex flavors and to its distinct sensory properties. The increasing demand for cocoa and its rising price urges the research for cocoa substitutes. A potential substitute for cocoa is carob. Carob is the fruit of an evergreen tree (Ceratonia siliqua L.) cultivated in the Mediterranean area, well known for its valuable locust bean gum and also for carob powder and syrup that are obtained from carob pulp. Cocoa beans and carob pods contain various phytochemicals including polyphenols, proteins and amino acids, fatty acids, carbohydrates and fiber. Phytochemicals represent an important source of nutrients and compounds that are beneficial to human health. In this review, phytochemicals in cocoa beans and carob pods and their impact on human health are reviewed. The bioactive compounds that are present in carob, in conjunction with the cocoa-like flavors and unique sensory properties that are enhanced by carob powder roasting, underline carob’s potential to substitute cocoa in various food products. These food applications are discussed in this review.
... with 95 mg/100g represented by ellagitannins and gallotannins. Phenolic compounds are known as powerful antioxidants [SAURA CALIXTO, 1988, AVALLONE et al., 1997 . ...
... It also contains appreciable amounts of fiber (up to 40%), proteins (2 to 7%) and low fat content (0.9 to 1.3%) [6,[14][15][16][17][18][19][20][21]. In addition to its nutritive qualities, the pulp contains more than 1.5% of condensed tannins, which are widely used as extracts in nutrition and medicine [22][23][24]. ...
... Carob dietary fiber is unique in its composition due to the presence of high amounts of polyphenols, mainly tannins. About 50% of the weight of the carob dietary fiber corresponds to polyphenols (Saura-Calixto 1988), and this makes it a different fiber than the other dietary fiber sources. These polyphenols are condensed tannins (proanthocyanidins), formed by groups of flavan-3-ol and their gallic esters, gallic acid (Avallone and others 1997), catechins, epicatechin gallate, epigalocatechin gallate, and quercetin glycosides (Owen and others 2003). ...
Carob (Ceratonia siliqua L.) is well known for its valuable locust bean gum obtained from the carob seeds. Separation of seeds from the pod leaves behind the carob kibble which is a good source of dietary fiber, sugars, and a range of bioactive compounds such as polyphenols and pinitol. Bioactive compounds present in carob kibble have been found to be beneficial in the control of many health problems such as diabetes, heart diseases, and colon cancer due to their antidiabetic, antioxidant, and anti-inflammatory activities. Carob kibble has substantial potential to be used as a food ingredient. This article focuses on the composition, health benefits, and food applications of carob kibble.
... Semejantes conclusiones han sido puestas de manifiesto por Kumar y Vaithiyanathan (1990) señalando importantes reducciones en la palatabilidad, ingestión voluntaria de alimento y digestibilidad de la materia seca y la proteína, en animales en pastoreo alimentados con hojas de árboles de diferentes contenidos en Taninos. Saura-Calixto (1988), al estudiar el efecto de los Taninos condensades de la Pulpa de Garrofa en el análisis de la Fibra Dietética, observó que aproximadamente el 94% de los compuestos de tipo fenólico se encuentran en el residuo insoluble del análisis de la Fibra Dietética, lo que indica claramente su baja digestibilidad. ...
... The flavonoids content is granted with [4] who found that carob contained between 0.41 and 0,48mg/g DM of flavonoids against by [24] and [23] have shown that the rate could be higher flavonoids with 1,02mg/g DM and 3,33mg/g DM, respectively, in addition to 9 different flavonoids were detected by [35] represented mainly by myricetin (0,148mg/g of extract). Condensed tannins, the hydrolysable tannins our results are much lower than those of [28] with 1.3% and lower than those of [3] with 0.95 mg/g represented by ellagitannins and gallotannins. ...
The carob tree (Ceratonia siliqua L.) is native to Mediterranean countries, it is robust and
rustic. The carob tree is cultivated for its pods, abundant and rich in sugar at maturity, they are
crushed with seeds into powder for live stock feed. The objective of this study was to evaluate
the morphological characterization of the carob tree and the chemical composition of the fruit
(pulp and seed).We has found that the leaf has a length 15,42cm, a width 10,88cm, a petiole
length 3,67cm and 9±1 leaflets. The leaflet has a length and a width corresponding to 5,59cm
and 3,95cm. The pulp of Marrakech (P5) has the highest rate with 52, 52% sugar. For fiber,
pulp Marrakech (P7) contains the most with 10, 90%. On secondary metabolites , the rate of
total phenols is significant enough, the order of 5,36 mg/g of dry matter for the pulp of Fez,
which is 3,74mg/g for seeds of Fez, followed by the rate of flavonoids , which is 0,48 m /g for
pulp of Khemisset (P4), hydrolyzable tannins, with a maximum of 0,07mg/g for the pulp and
seed of Meknes (P3) and pulp of Khemisset (P4).
... The flavonoids content is granted with [4] who found that carob contained between 0.41 and 0,48mg/g DM of flavonoids against by [24] and [23] have shown that the rate could be higher flavonoids with 1,02mg/g DM and 3,33mg/g DM, respectively, in addition to 9 different flavonoids were detected by [35] represented mainly by myricetin (0,148mg/g of extract). Condensed tannins, the hydrolysable tannins our results are much lower than those of [28] with 1.3% and lower than those of [3] with 0.95 mg/g represented by ellagitannins and gallotannins. ...
The carob tree (Ceratonia siliqua L.) is native to Mediterranean countries, it is robust and
rustic. The carob tree is cultivated for its pods, abundant and rich in sugar at maturity, they are
crushed with seeds into powder for live stock feed. The objective of this study was to evaluate
the morphological characterization of the carob tree and the chemical composition of the fruit
(pulp and seed).We has found that the leaf has a length 15,42cm, a width 10,88cm, a petiole
length 3,67cm and 9±1 leaflets. The leaflet has a length and a width corresponding to 5,59cm
and 3,95cm. The pulp of Marrakech (P5) has the highest rate with 52, 52% sugar. For fiber,
pulp Marrakech (P7) contains the most with 10, 90%. On secondary metabolites , the rate of
total phenols is significant enough, the order of 5,36 mg/g of dry matter for the pulp of Fez,
which is 3,74mg/g for seeds of Fez, followed by the rate of flavonoids , which is 0,48 m /g for
pulp of Khemisset (P4), hydrolyzable tannins, with a maximum of 0,07mg/g for the pulp and
seed of Meknes (P3) and pulp of Khemisset (P4).
... The NEPP content of several plant foods and extracts has been determined using the methodologies described above. For instance, non-extractable proanthocyanidins, which are widespread among plant foods, have been determined (as NEPP-class II) in cocoa powder (602 mg/100 g dw) (Hellström et al., 2009), cranberry pomace (1685 mg/100 g dw) (White et al., 2010), cider waste (300 mg/100 g dw) and carob pods (18,000 mg/100 g dw) (Saura Calixto, 1988). Similarly, the hydrolyzable phenolic compounds content (as class II NEPP) of several plant foods and by-products has been estimated, such as blackcurrant pomace (41 mg/100 g dw) (Kapasakalidis et al., 2006) and red ginseng (2 mg/100 g dw) (Jung et al., 2002). ...
Polyphenol content in plant foods is usually considered as that found in their corresponding aqueous-organic extracts. Nevertheless, polyphenols found in these extracts would correspond only to a fraction of these phytochemicals, the extractable polyphenols (EPP). The extractions leave a residue, commonly neglected, containing an understudied fraction of plant foods polyphenols, the so-called non-extractable polyphenols (NEPP). NEPP comprise polyphenols belonging to different classes, such as macromolecular polyphenols or single polyphenols associated with cell wall macromolecules. Although only a minor part of the existing literature on polyphenols in plant foods have dealt with NEPP, the existing data show that they are even more abundant than EPP in many plant foods. The present chapter aims to provide an overview of NEPP in plant foods, including their nature, procedures for their isolation, current analytical methods, content in several foods and extracts, and potential applications.
... Nevertheless, the results constitute evidence of an appreciable presence of NEPP in plant foods and of their contribution to total polyphenol intake. Apple 37 -43 (31) Quince 48 (32) Banana 980 (SD 45)* (27) Apple pomace 18 -23 (33) Cranberry pomace 1685 (34) Cocoa powder 602 (SD 13) (35) Carob pod 180 (36) Hydrolysable phenolics ...
Current research on dietary antioxidants misses the so-called non-extractable polyphenols (NEPP), which are not significantly released from the food matrix either by mastication, acid pH in the stomach or action of digestive enzymes, reaching the colon nearly intact. NEPP, not detected by the usual analytical procedures, are made up of macromolecules and single phenolic compounds associated with macromolecules. Therefore, NEPP are not included in food and dietary intake data nor in bioavailability, intervention or observational studies. The present paper aims to provide an overview of dietary NEPP - nature, occurrence in diet, metabolic fate and possible health effects. NEPP are a relevant fraction of dietary polyphenols exerting their main biological action in the colon, where they are extensively fermented by the action of microbiota, giving place to absorbable metabolites. NEPP exhibit different potential health-related properties, in particular in relation to gastrointestinal health, such as increases in antioxidant and antiproliferative capacities, reduction of intestinal tumorigenesis and modification of gene expression, as observed in different animal models. Further research into NEPP may provide a better understanding of the health effects of dietary antioxidants.
... Fructose (0.54-1.4%) was identified as the lowest amount of sugars in the carob genotypes. Sugar content of carob can be changed based on the geographical diversity (Würsch et al., 1984;Saura-Calixto, 1988;Avallone et al., 1997). In another study reported by Karkacier and Artik (1995), the authors implied that when the fruits are ripe enough to be harvested, it has 91-92% total dry matter and 62-67% total soluble solids, which consists of 34-42% sucrose, 10-12% fructose and 7-10% glucose. ...
The research was carried out on apple, peach, nectarine and apricot cultivars during 1992-1994. In this work, the cold hardiness of apple, peach, nectarine and apricot cultivars were investigated. For this purpose, the relationship between the car- bonhydrates or plant nutrient elements and the cold hardiness of the cultivars were investigated by viability tests. According to the results, apples and among them Granny Smith and Starkrimson cultivars, J.H. Hale and Monroe peach cultivars among the peaches, Maygrand among the nectarines and Precoce de Colomer and Canino apricot cultivars among the apricots were found as the most cold resistant cultivars. This cultivars were found to be more resistant in January and the highest amount of total sugar and macro element contents such as nitrogen, phosphorus and potassium were determined especially in apple cultivars but no direct relationship was found between the cold hardiness and nitrogen content of peach, nectarine and apricots.
... The main classes of non-starch polysaccharides are cellulose, hemicelluloses, pectins, and other hydrocolloids. However, some authors (Saura-Calixto F, 1988) have reported that a significant part of the starch content in foods, namely, resistant starch (RS) escapes digestion and absorption in the human small intestine, along with other dietary substances not included in the DF definition such as protein, oligosaccharides and certain polyphenolic compounds (Cummings & Macfarlane, 1991; Bravo, 1998; SauraCalixto F, 1988; Asp et al., 1996; Prosky, 1999). In general, the definition and delimitation of DF has been much debated and related both to physiological considerations and to methods that can be used for DF analysis in foods (Asp, van Amelsvoort, & Hautvast, 1996; Englyst, H.N. and Hudson, G.J. Englyst & Englyst, 2005; Englyst, Liu, & Englyst, 2007 Therefore, DF constitutes a heterogeneous group of compounds. ...
Many by-products originating from cereal, fruit and vegetable industries contain quite high amounts of dietary fiber (DF), which play an important role in maintaining the healthy state of the human body. Nevertheless, huge proportions of these by-products are still underutilized as feed ingredients, to generate energy within an anaerobic digestion plant or even landfilled. One of the biggest hindrances in the valorization of such by-products is their very low soluble dietary fiber (SDF) to insoluble dietary fiber (IDF) ratios, impairing their nutritional functionality, palatability and technological applicability. Therefore, it is of interest to develop methods that can enhance the SDF to IDF ratio and that can be applied to the by-product streams of the food industry, enabling better valorization perspectives for human nutrition purposes. In this regard, the review paper provides an overview of existing technologies to modify the SDF to IDF ratio in by-products of the food industry by means of physical, chemical and biological treatments. For each type of treatment, available data on application examples including achieved increases in SDF contents are given. Additionally, a comparative discussion regarding the advantages and disadvantages of these methods is provided.
Flavonoid based proanthocyanidins and cinnamyl alcohol based lignins are chemically complex phenolic oligomers/polymers that are found in food plants. Although structurally very different, these two biopolymers are often not distinguished, for example, in the (quantitative) compositional analysis of cell walls and dietary fiber. Here, we analytically distinguish lignin and proanthocyanidins in dietary fiber samples by using degradative and nondegradative techniques and provide information about their occurrence, abundance, and structural characteristics in seeds of chokeberries, cranberries, raspberries, red currants, and grapes. These data revealed that the seeds of botanically diverse fruits largely differ in terms of their phenolic fiber polymers. The mostly hardened tissue of the seeds is not necessarily based on lignified cell walls. For example, red currant and chokeberry seeds almost exclusively contain proanthocyanidins, and raspberry seeds were clearly lignified (G-H-lignin) but did not contain proanthocyanidins. Our data also allows for estimating the bias of proanthocyanidins on different approaches of lignin analysis.
Current research on dietary polyphenols is mostly focused on the so‐called extractable polyphenols (EPP), those released from the food matrix by several solvent combinations. However, this ignores a relevant fraction of polyphenols remaining in the residues of those extractions, the nonextractable polyphenols (NEPP) or macromolecular antioxidants. These are either polymeric structures (mostly high molecular weight proanthocyanidins) or small phenolic structures closely linked to macromolecules such as proteins or dietary fiber. This partial approach to these dietary bioactive constituents may hamper our understanding of the relevance of dietary polyphenols. This chapter provides an overview of the current knowledge of NEPP. In particular, the following aspects are explored: strategies for the release and analysis of NEPP; contribution of these compounds to total polyphenol content in foods and therefore to total polyphenol intake in different populations; evidence of their metabolic fate as well as specific features compared to those of EPP; mechanism of biological action (antioxidant effects, modulation of colonic microbiota, biological activities of NEPP‐derived metabolites, synergy with dietary fiber); evidence of biological activity (considering both local effects in the digestive tract and systemic effects through their metabolites). Finally, the chapter provides some perspectives on the main aspects that should be considered in order to advance scientific knowledge on NEPP in the future.
Scientific monograph about taxonomy, ethnobotany, ecology, genetic variability, phytochemical characteristics and utilization of carob tree (Ceratonia siliqua L.) and bay laurel in Croatia.
The carob tree belongs to the nutrient plants and it is known since antiquity as a native plant of Greece. Its scientific name Ceratonia siliqua, originates from the Greek word "keraton" which means "horn", and which indicates the shape of its fruit. The carob tree is an evergreen, long-lived, polygamous, monoecious or dioecious. It is easily cultivated and thrives in all types of soil, except the humid and non-affluent. The wood, the bark and the leaves of carob have different uses. The fruit of the carob tree, the carob, is a lobe and it is 10-30 cm long and 2-3 cm wide with a brown and leathery exocarp and a fleshy and juicy mesocarp, in which 8 to 16 oval, flattened, hard and shiny reddish seeds are enclosed. The collection of the fruits must be finished before the winter rains. The fruits fall from the tree by themselves or by caning. A 6 years old carob tree can produce 2.25 kg carobs, while a 12 years old tree can produce 45 kg or more. The annual Greek carob production for the year 2005 was 14,816 tons, while the average yield was 9.8 kg/tree. The world carob production is about 315,000 tons/year. The carobs have low total fat and crude protein content, but high sugar content. The carobs' characteristic odor is due to their isobutyric acid content (1.3%). Furthermore, they include an unusually large amount of tannins, 16-20% of which are polyphenols and 27-50% of which are bound with cellulose. The tannins are a complex group of secondary metabolites of plants and are separated from other polyphenol compounds due to their ability to create sediment with proteins. The presence of tannin in feed reduces the nutrients' digestibility and has a negative effect on body weight gain. However, tannins can also have positive effects depending on their biological potency, because they have the ability to prevent bacterial, fungal and yeast growth. Carobs and their by-products have a considerable fibre content (average 8%) and therefore they can be included in supplementary ruminant rations up to 20% - 30%. Experiments carried out by adding carobs in broiler feeds resulted in decreased body weight gain and increased feed conversion ratio, probably because of the high cellulose and tannin content of the carob. Nevertheless, if the broiler's ration is enriched with fats or oils and synthetic amino acids, these birds show normal weight gain, but with a high feed conversion ratio. The carobs can be included up to 10% - 20% in the ration of pigs. Also, since the carobs have high sugar content, they can increase the feed consumption of the piglets and they can replace other sugar feeds with high sugar content (dextrose, starch, milk powder) without adversely affecting the feed intake. Greece produces a considerable quantity of carobs every year, therefore a part of this production could be utilized as animal feed
The beneficial effects of wine drinking are at present acknowleged by the scientific community, for the reason of the polyphenolic content of wine which causes a lower incidence of cardiovascular diseases. The health treasure kept in wine derives from its raw materials; grapes, in fact, contain high amounts of polyphenols. However, only a fraction of the polyphenolic content of grapes is actually transferred to wine. After the winemaking process, indeed, only a fraction of total grape polyphenols is found in wine, while the rest remains in grape skin, stem and seeds. The by-products of winemaking are then extremely rich in compounds that, due to their relevant biological properties, could be exploited for industrial purposes, with applications in the nutritional, medical and cosmetic fields, as well as development of advanced solar cells and related devices. Hence, the exploitation of such a polyphenol treasure, which is commonly disregarded, could provide an economic boost to the whole industry of winemaking countries or regions. An additional achievement obtained by the treatment of winemaking residuals is the possibility of alleviating problems of residual disposal. Most of these materials, in fact, should be treated as special wastes, according to current regulations.
The preparation of a traditional dairy product named mekika is well known in some specific areas of Lebanon. The mekika is produced by coagulating milk with green carob pods extract. Our study is done in the concept of preservation of the culinary traditions of the country by giving scientific information needed to support this product and allow its manufacture at industrial scale. Our objective is to study the chemical reactions implied in milk coagulation and the technological characteristics of the dairy product obtained. The importance of this traditional technology is assessed by its comparison with other practices using classical techniques for milk coagulation as for example proteolytic enzymes such as chymosin. This study is conducted also on different types of milk including cow, ewe, sheep and camel milk.
The carob tree belongs to the nutrient plants and it is known since antiquity as a native plant of Greece. Its scientific name Ceratonia siliqua, originates from the Greek word “keraton” which means "horn", and which indicates the shape of its fruit. The carob tree is an evergreen, long-lived, polygamous, monoecious or dioecious. It is easily cultivated and thrives in all types of soil, except the humid and non-affluent. The wood, the bark and the leaves of carob have different uses. The fruit of the carob tree, the carob is a lobe, and it is 10-30 cm long and 2-3 cm wide with a brown and leathery exocarp and a fleshy and juicy mesocarp, in which 8 to 16 oval, flattened, hard and shiny reddish seeds are enclosed. The collection of the fruits must be finished before the winter rains. The fruits fall from the tree by themselves or by caning. A 6 years old carob tree can produce 2.25 kg carobs, while a 12 years old tree can produce the 45 kg or more. The annual Greek carob production for the year 2005 was 14,816 tons, while the average yield was 9.8 kg / tree. The world carob production is about 315,000 tons / year. The carobs have low total fat and crude protein content but high sugar content. The carobs’ characteristic odor is due to their isobutyric acid content (1.3%). Furthermore, they include an unusually large amount of tannins, 16-20% of which are polyphenols and 27-50% of which are bound with cellulose. The tannins are a complex group of secondary metabolites of plants and are separated from other polyphenol compounds due to their ability to create sediment with proteins. The presence of tannin in feed reduces the nutrients’ digestibility and has a negative effect on body weight gain. However, tannins can also have positive effects depending on their biological potency, because they have the ability to prevent bacterial, fungal and yeast growth. Carobs and their by-products have a considerable fibre content (average 8%) and therefore they can be included in supplementary ruminant rations up to 20% - 30%. Experiments carried out by adding carobs in broiler feeds resulted in decreased body weight gain and increased feed conversion ratio, probably because of the high cellulose and tannin content of the carob. Nevertheless, if the broiler’s ration is enriched with fats or oils and synthetic amino acids, these birds show normal weight gain, but, with a high feed conversion ratio. The carobs can included up to 10% - 20% in the ration of pigs. Also, since the carobs have high sugars content, they can increase the feed consumption of the piglets and they can replace other sugar feeds with high sugar content (dextrose, starch, milk powder) without adversely affecting the feed intake. Greece produces a considerable quantity of carobs every year, therefore a part of this production could be utilized as animal feed.
An improvement in oxidative status is associated with a reduction in the incidence of several chronic diseases. However, daily intake of antioxidants in Western diets is decreasing. This study evaluates the effect of daily consumption of an antioxidant-rich juice (ARJ) on oxidative status, cardiovascular disease risk parameters, and untargeted plasma and urine metabolomes. Twenty-eight healthy young adults participated in an 8-week clinical trial by drinking 200 mL of ARJ (pomegranate and grape) daily. At the end of the study, the subjects showed a significant decrease (-29 %) in plasma lipid oxidation (malondialdehyde concentration), and a significant increase (+115 %) in plasma antioxidant capacity. Plasma and urine metabolomes were also significantly modified and some ions modified in urine were identified, including metabolites of polyphenols, ascorbic acid and biliary acids. No significant changes were observed in lipid profile, inflammation, blood pressure or glycaemia. These results show that incorporating antioxidant-rich beverages into common diets may improve oxidative status in healthy subjects.
Prosopis species are generally fast-growing, drought-resistant, nitrogen-fixing trees or shrubs. Fruits of Prosopis spp are indehiscent pods, where pericarp is formed by the epicarp, light brown in colour, and fibrous nature; the mesocarp known as pulp, which is rich in sugars; and the endocarp. The aim of this work was to obtain a fibre concentrate from the pods of Prosopis chilensis Mol. (Stuntz) and to determine the chemical, physical, and technological properties of the pod flour (PF) and of a fibre concentrate or pod purified flour (PPF). Acetone, ethanol, and water at different conditions of time and temperature were used in the purification process. PF showed 53.7 g/100 g of total sugar content, 4.2 g/100 g of reducing sugar content, 41.8 g/100 g of total dietary fibre, 35.8 g/100 g of insoluble fibre, and 6.0 g/100 g of soluble fibre content. The PPF has a total sugar content of 3.8 g/100 g, reducing sugar content of 2.2 g/100 g, total dietary fibre content of 80.8 g/100 g, insoluble fibre content of 75.1 g/100 g, and soluble fibre content of 5.7 g/100 g. The scanning electron microscopy analysis showed the existence of voids in the structure of PPF flour, which reveals the efficiency of the purification process with a high decrease in the total sugar content.
Residues from orange juice extraction are potentially an excellent source of dietary fiber (DF), because this material is rich in pectin and may be available in large quantities. Chemical and physical characteristics of DF obtained from orange pulp were determined for three varieties of oranges. Total DF content reached quite high values: 35.4–36.9% dry matter (DM). Orange DF was rich in pectins (15.7–16.3% DM), as well as cellulose and hemicellulose (16.6–18.1% DM) and lignin (2.2–3.0% DM). The product showed a relatively high water holding capacity (7.3–10.3 g water/g fiber), high oil absorption property (0.9–1.3 g oil/g fiber) and low caloric value (3519–3735 cal/g). Chemical analyses of orange DF concentrate showed low contents of protein, fat and ash (8.1–10.1%, 1.5–3.0% and 2.6-3.1% DM, respectively). The orange DF color ranged from yellow to light orange. These characteristics suggested many potential applications such as, clouding agent in beverages, thickener and gelling agent as well as binder, texturizer and low calorie bulk ingredient.
Insoluble and soluble dietary fibre (DF) fractions of peach DF concentrate, obtained by an enzymatic-chemical method, were analysed for neutral sugars, uronic acids and Klason lignin. Proximate composition, energy value, colour and water- and oil-holding capacities were also determined. Total DF constituted 31–36% dry matter (DM) of the concentrate and insoluble DF was its major fraction (20–24% DM). The high proportion of soluble fraction (11–12% DM) in the peach DF concentrate, in comparison with cereal brans, was noticeable. Insoluble and total dietary fibre contents significantly decreased throughout the harvest time of the original fresh fruit. Results suggested that peach DF concentrate may be not only an excellent DF source but an ingredient in the food industry because it showed a high affinity for water (9.12–12.09 g water/g fibre) and low energy (3.723–3.494 kcal/g). However, the use of this material could affect the colour and pH of the final product.
Most research in the field of dietary polyphenols or phenolic compounds use a chemical approach focusing exclusively polyphenols extracted from plant foods with organic solvents. However, an appreciable part of polyphenols are not extracted with organic solvents and thus are ignored in biological, nutritional and epidemiological studies. Recent reports have shown that these non-extractable polyphenols (NEPP) are a major part of total dietary polyphenols and they exhibit a significant biological activity. A physiological approach is proposed on the basis that the bioavailability and health related properties of polyphenols depend on its solubility in intestinal fluids, which is different from their solubility in organic solvents. This article tries to clarify the concept of non-extractable polyphenols, distinguishing between chemical approach and physiological approach and pointing out the main qualitative and quantitative differences between them. It is stressed that literature articles and databases refer only extractable polyphenols. A greater attention to non-extractable polyphenols may fill the current gap in the field of dietary polyphenols.
A comparative study between dietary fiber (DF) and polyphenols (PP) in terms of degradability and physiological properties was performed. Eight groups of Wistar rats were fed either a control diet free of DF and PP or diets containing DF constituents [cellulose (C), pectins (P), and lignin (L)] or PP, both soluble [catechin (CA) and tannic acid (TA)] and insoluble [condensed tannins (CT)]. A significant increase in the total stool output and in the water and fat content of feces was observed. Protein digestibility was significantly reduced. Intestinal degradation of the soluble compounds (P, CA, and TA) was almost complete. C was partially digested; L and CT were highly resistant. In vitro fermentation assays were performed, showing the different susceptibilities of the DF constituents and the polyphenolic compounds to fermentation and the inhibitory effect of TA and L on colonic microflora.
The composition of mesquite pods (Prosopis pallida L) (PP), a legume cultivated in the large desert areas of Peru, was studied. These fruits have at the present time very little practical or commercial use. Taking into account the morphological and compositional similarities to Mediterranean carob pods (Ceratonia siliqua L) (CS), which are widely used in the food industry, some applications of PP are considered. PP shows better nutritional properties than CS, mainly owing to its lower polyphenolic content and higher protein digestibility.
ABSTRACTA rapid methodology (less than 90 min) is described for the qualitative and quantitative analysis of 2,5-dimethyl-4-hydroxy-3 (W)-furanone (furaneol), furaneol-β-glucoside, and 2,5-dimethyl-4-methoxy-3 (2H)-furanone (mesifurane) in strawberries. These compounds were resolved by HPLC with a RP C18 column, using acetate buffer and methanol as binary mobile phase and detection at 280 nm, and confirmed by GC-MS. The aqueous extraction procedure gave an average recovery of these compounds from strawberries > 90%, with detection limits: 0.14 furaneol, 0.05 furaneol-β-glucoside, and 0.36 μg/rnL mesifurane.
The possible degradation of non-extractable condensed tannins (NECT) within the intestinal tract and their effect on faecal weight and composition was studied. Two groups of male Wistar rats were fed either a NECT-free control diet, or a diet containing 100 g carob pod concentrate kg−1 (53 g NECT kg−1 dry matter) for 5 weeks. A slight effect of NECT on growth rate was observed in the fifth week. The NECT diet did not affect food intake. Significant increases of total faecal output as well as water, nitrogen and fat excretion were observed. NECT were not degraded in the intestinal tract, since they were quantitatively recovered in faeces (98 ± 1%). Since the usual spectrophotometric methods gave contradictory results on NECT levels in the diet and faeces, an alternative method based on Klason lignin residues was used.
The levels of condensed tannins in tannin-protein complexes dried at 50°C or at 100°C for 2 h, 4 h and 24 h, determined by butanol-HCl reagent, were significantly lower compared to those in freeze-dried or undried complexes. On the other hand, condensed tannins in the fibre fractions (neutral detergent fibre and acid detergent fibre) were statistically similar in samples freeze-dried or dried at 50°C. Significantly lower levels of condensed tannins were observed in fibre fractions dried at 100°C as compared to freeze-dried fibre fractions. The results suggest that for accurate determination of condensed tannins bound to fibre fractions or present as tannin-protein complexes, the fibre fractions or the samples containing tannin-protein complexes should be freeze-dried.
The effect of roasting on dietary fiber fractions of cocoa beans was determined by gravimetric and fractionation procedures after enzymatic treatment. Roasting had no notable effect on total dietary fiber content (TDF). Components of insoluble dietary fiber (IDF) became redistributed after roasting. One of the largest changes was a sharp increase of Klason lignin. The noted decrease in sugar content without a change in IDF suggested that neutral sugars and uronic acids may be involved in Maillard polymer formation. Soluble dietary fiber (SDF) did not show large variations. Undigestible protein in IDF increased after roasting.
Cider wastes are rich in polysaccharides and can be considered a suitable source of dietary fibre (DF). The measurement of DF as ‘non-starch polysaccharides’ (48·3% dry matter), and as ‘non-starch polysaccharides plus lignin’, (63·3%), is performed by spectrophotometric and AOAC procedures. A good agreement between both methods for polysaccharide content is found. Correction for condensed tannins (3·1% dry matter) is made. The Klason lignin residue contains protein and condensed tannins.
Dietary fibre (DF) determinations were carried out on grape pomaces by AOAC and spectrophotometric procedures. Insoluble dietary fibre (IDF) and Klason lignin (KL) residues contained appreciable amounts of condensed tannins (CT) and resistant protein (RP). The presence of CT and RP in the residues obtained after the successive action of amylase, protease and amyloglucosidase and chemical treatments with H2SO4 and HCl-triethyleneglycol, together with similar data previously reported for other samples could be considered in a wider definition of the DF complex as ‘indigestible polysaccharides, phenolic polymers and resistant protein’. The term ‘phenolic polymers’ includes both lignin and CT.
The process of convective drying was evaluated in terms of the bioactive compounds contained in nopal samples before and after dehydration. Total polyphenol, flavonoid, flavonol, carotene and ascorbic acid contents were determined in undehydrated and dehydrated samples. Two drying temperatures (45 and 65 °C) and two air flow rates (3 and 5 m s(-1) ) were evaluated. The rheology of samples under the best drying conditions was also studied, since it provides important information regarding processing (mixing, flow processing) as well as the sensory attributes (texture) of rehydrated samples.
Non-Newtonian shear-thinning behaviour was observed for samples dried at 45 °C, while samples dried at 65 °C showed shear-thickening behaviour, possibly caused by thermal chain scission of high-molecular-weight components.
The best conditions for bioactive compound preservation were a drying temperature of 45 °C and an air flow rate of 3 m s(-1) , resulting in 40.97 g phenols, 23.41 g flavonoids, 0.543 g β-carotene and 0.2815 g ascorbic acid kg(-1) sample as shown in table 3.
Although the fruit of the carob tree (Ceratonia siliqua L. Fabaceae) is nutritious and widely available in Turkey, especially in West and South Anatolia, much remains to be learned about its nutrient composition. The main goal of our study was to determine if there are differences in the content of certain nutrients in commercially-prepared carob flour (CPCP) and domestic or home-prepared carob powder (HPCP). Sucrose was the main sugar in CPCP and HPCP. Total protein was 40% lower in CPCP than HPCP due mainly to decreases in the content of several essential amino acids. However, except for lysine in CPCP, HPCP and CPCP compared favourably to a WHO protein standard. There were large differences in terms of their content of the two essential fatty acids, linoleic and alpha-linolenic acid, and the linoleic acid/alpha-linolenic acid ratio was 3.6 for CPCP, and 6.1 for HPCP. Manganese and iron were 2.5-fold higher in HPCP than CPCP. This study demonstrates that carob flour prepared in either the household or industrially is a good source of many, but not all essential nutrients, and that commercial processing of carob fruit into flour seems to affect its content of several important nutrients.
Dietary fiber (DF) intakes in Western countries only accounts for about one-third of the substrates required for colonic bacterial cell turnover. There is a general trend among nutritionists to extend the DF concept to include all food constituents reaching the colon. In this line, a method to quantify the major nondigestible components in plant foods, namely, the indigestible fraction (IF), is presented. Analytical conditions for IF determination are close to physiological. Samples, analyzed as eaten, were successively incubated with pepsin and alpha-amylase; after centrifugation and dialysis, insoluble and soluble IFs were obtained. IF values include DF, resistant starch, resistant protein, and other associated compounds. IF contents determined in common foods (cereals, legumes, vegetables, and fruits) were higher than DF contents. Calculated IF intakes were close to the estimated amount of substrates reaching the colon. IF data could be more useful than DF data from a nutritional point of view; therefore, IF is proposed as an alternative to DF for food labeling and food composition tables.
A procedure is described for the measurement and characterisation of total non-starch polysaccharides in plant foods by gas-liquid chromatography of individual sugars as alditol acetates. Starch, including that resistant to gelatinisation in boiling water, is dispersed with dimethyl sulphoxide and then hydrolysed with α-amylase and pullulanase. Starch-free material is hydrolysed with sulphuric acid and the released neutral sugars are measured as alditol acetates by using N-methylimidazole in order to catalyse the acetylation. Uronic acids are measured by a spectrophotometric method. The procedure is a modification of a more comprehensive method reported previously. It is relatively rapid and simple compared with gravimetric procedures, is applicable to a wide range of foodstuffs, can be carried out without special expertise in carbohydrate chemistry and is suitable for routine laboratory use.
Locust bean gum is a vegetable mucilage which is manufactured in some European countries and exported to America. This paper presents information on some colloidal and chemical properties of this galactomannan. The viscosity of aqueous dispersions of locust bean gum increases very much on heating. The high viscosity of the gum solutions is explained by the assumption of stretched chain molecules; it is assumed that the galactose side groups cause uncoiling of the polymannose chain. Quantitative coagulation experiments have been made and compared with those of many other hydrocolloids. The gelling with borax is explained as a cross-linking reaction. Locust bean gum increases the gelling strength of agar gels. In a commercial enzyme preparation two "carubinases" which hydrolyze the two different glycosidic linkages of the polysaccharide have been found. Locust bean gum can form derivatives. The reaction products of locust bean gum with acetic anhydride and with epichlorohydrin were especially studied.
Distribution of α-d-galactopyranosyl side-chain groups in two galactomannans, guaran and locust-bean gum, was determined by measurement of the O-acetyl-O-methyl-d-mannitol derivatives obtained from the corresponding primary C-p-tolylsulfonyl polysaccharide derivatives. The O-acetyl-O-methyl-d-mannitol derivatives were produced by β-elimination and methylation, with sodium (methylsulfinyl)methide and methyl iodide, of the primary C-p-toluenesulfinylated galactomannans, followed by sequential acid hydrolysis, reduction, and acetylation of the partially degraded p-tolyl sulfones. The results indicated that side-chain units of guaran are alternately disposed along the d-mannan backbone, whereas those of locust-bean gum are disposed in uniform blocks along the backbone.
After depolymerisation to n ∼20-40, galactomannans from guar, carob (locust bean), lucerne and clover seeds gave good 1H- and 13C-n.m.r. spectra. The resonances of the anomeric protons and the twelve carbon atoms were fully resolved and easily identified. Measurement of the ratios of corresponding peak-areas gave results for monomeric composition (Gal: Man ratio) in good agreement with those of chemical analysis. Resonances from C-4 of d-mannose residues were split, in evident dependence upon the nearest-neighbour probabilities (“diad frequencies”) Of d-galactosyl groups along the mannan chains. The relevant peak-area ratios gave values for these probabilities that were roughly consistent with a random arrangement of d-galactosyl groups in all four galactomannans, but they do not exclude the possibility of more complex kinds of arrangement.
This review attempts to provide a current summary of literature concerning the chemistry of tannins and their various adverse effects upon ruminant feed quality. These include the chemical nature of hydrolyzable and condensed tannins, their occurrences in numerous feeds and fodders, their interaction with proteins, and subsequent effects upon voluntary feed intake, dry matter and protein digestibility, and rumen metabolism. In addition, the processing of tannin-rich ruminant feed for their increased utilization is also discussed.
Three related methods, A-C, are described for analysis of dietary fiber (DF). Homogenized and/or milled foodstuff is extracted with 80% ethanol and light petroleum ether. The extracted residue is analyzed directly for the DF and starch content (method B) or treated further with thermostable α-amylase at 96°C and amyloglucosidase at 60°C. Insoluble and soluble DF components were then separated by centrifugation and, respectively, dialysis and freeze-drying of the supernatant (method A). Alternatively, insoluble and soluble DF components were isolated together by precipitation of soluble fiber in 80% ethanol and subsequent centrifugation (method C). Neutral polysaccharide constituents were analyzed as alditol acetates, uronic acids by a decarboxylation method, and Klason lignin by gravimetric techniques. Starch was determined enzymatically. A satisfactory correlation between the different DF methods was observed for several food samples.
Determination of the tannins, pectins, hemicellulose, cellulose, nitrogen, mineral elements, total and reducing sugars and fat contents was carried out on carob pods from Mallorca, Spain. The results are compared with data from the literature. A survey of papers on the composition and practical applications of carob pods is included.
Methods for the quantitative analysis of anthocyanins, leuco-anthocyanins, flavanols and total phenols in plant tissue extracts are critically examined and suitable modifications of existing methods are described.
1.1. The two major urinary metabolites of rats ingesting carobs (Ceratonia siliqua) and carob fractions were chromatographically identified as gallic acid and 4-O-methylgallic acid.2.2. These metabolites probably originate from free gallic acid in green carob pods, or from the ester-linked gallates in the tannin fraction.3.3. The catechin moiety of condensed carob tannins does not undergo metabolism in the rat.
Cassava (Manihot esculenta, Crantz), an important tropical root crop, is considered to have a good potential for use as a forage because leaf blades generally contain <20% crude protein (CP). However, neutral-detergent fibre (NDF) obtained from cassava leaf blades contains condensed tannins (CTs) and high levels of CP. The amount of CP in the NDF that is insoluble when treated with pepsin or protease is highly correlated with the amount of CTs in the NDF. CTs in the NDF are rich in prodelphinidin. CTs may be an important factor limiting the nutritive value of cassava forage.
Carob pod fiber containing 44.4% highly polymerized tan nins was fed to rats in a purified diet in order to study its effect upon the concentration of cholesterol and lipids in the plasma and liver, and the fecal excretion of sterols and bile acids. The Carob fiber complex reduced significantly the protein utilization, probably by non-specific binding of protein by carob tannins. Rats fed diets containing 5 and 15% fiber ex creted the same amount of sterols but 3 and 5 times more bile acids, respectively, than did rats fed the fiber-free diet. The concentration of bile acids in the feces, however, remained unchanged due to the increased weight of the feces in rats fed fiber-containing diets. Bacterial degradation of cholesterol was reduced strongly in these two groups. Supplementation of the diet with cholesterol increased the fecal sterol and bile acid excre tions in rats fed fiber-free diets, but these excretions were even more in creased in the 5 and 10% fiber groups. The concentration of the bile acids in the feces was unchanged in the three groups that received cholesterol. In vitro studies demonstrated that carob fiber adsorbed appreciable quanti ties of bile salts. A diet containing at least 10% fiber was required to reduce the elevation of liver cholesterol and total lipid levels from dietary choles terol, but it did not prevent the increase of the plasma cholesterol level. Our data suggest that carob fiber has an influence on cholesterol turnover by decreasing the absorption of bile acids and cholesterol but the latter only in the case of cholesterol-fed rats. J. Nutr. 109: 685-692, 1979.
The factors affecting the stability, hydrolysis, reduction, acetylation, quantitation, and identification of the neutral sugars from vegetable fiber preparations have been studied critically and optimized. The recommended method offers a consolidation of the recent modifications of the alditol acetate procedure for the estimation of neutral sugars. The recovery of the sugars was tested by glc and ion-exchange chromatography. Also, the modified carbazole method of Bitter and Muir was adapted to make it applicable for the estimation of uronic acid content of fiber because uronic acid cannot be estimated quantitatively by the acetylation procedure. It is emphasized that the proposed method is applicable only to highly purified fiber preparations which are free of coprecipitated intracellular compounds. Also, the levels of pentoses and hexoses in the fiber must be well defined and a suitable correction made for their interference in the assay.
A gas chromatographic method was evaluated for the determination of food grade gums in dairy products, salad dressings and meat sauces. The gums studied were tragacanth, karaya, ghatti, carob, guar, arabic and xanthan gum. The extraction method included removal of fat followed by starch degradation then precipitation of protein. The isolated gums were hydrolysed with trifluoroacetic acid and the resulting neutral monosaccharides converted to their aldonitrile acetate derivatives for determination by gas chromatography. Recoveries from thirteen different commodities averaged 85%. However, the recovery of guar gum from ice cream and cold pack cheese was 42 and 50%, respectively. In a comparison of enzyme hydrolysis and iodine complexation for the removal of starch the former was simpler and provided cleaner extracts than the iodine treatment. Both gave similar results.
A new method for determination of uronic acids with meta-hydroxydiphenyl is introduced. It is simpler, quicker, more sensitive, and more specific than other methods, and it needs lesser amounts of fluid. It is recommended for determination of acid mucopolysaccharides in biological materials.
The degree of inhibition of trypsin, β-amylase and lipase by condensed carob tannins was determined, and compared with that caused by a glucoside of m-digallic acid. the carob tannins were strongly inhibitory to all the enzymes assayed; β-amylase was the most sensitive and lipase the least sensitive. Only in the case of lipase was the hydrolysable tannin a more active inhibitor than the condensed carob tannins. Polyvinyl pyrrolidone reactivated trypsin and lipsse, but not β-amylase.
The inhibitors were found to change the maximum reaction velocities of crystalline trypsin and β-amylase, indicating non-competitive reaction kinetics.
The present paper describes a simple method for the determination of the insoluble and soluble dietary fibres in food. In a first step, starch and proteins are removed by enzyme treatment. The insoluble dietary fibres are determined gravimetrically after centrifugation and washing of the residue with water, ethanol, acetone and diethyl ether. The water-soluble dietary fibres are recovered from the supernatant liquid of the centrifugation by dialysis, freeze-drying, and subsequent weighing. The method has been used for the determination of dietary fibres in by-products from the industry.
Saline extracts of the intestinal contents of 36 rats, which had been randomly allocated into six dietary groups, were assayed for trypsin, α-amylase and lipase. The activities of both trypsin and α-amylase were significantly reduced in rats consuming diets containing testa from Dylan, a coloured flowered variety of field bean, whilst those receiving diets containing testa from the tannin-free, white flowered variety Triple White had comparable activities with those on a control testa-free diet. Polyvinyl-pyrrolidone-saline extracts of the gut contents, however, had similar trypsin activity for all diets and it was concluded that the original observed reduction in digestive enzyme activity was due to the presence of field bean polyphenolics, which are known to be present in the testa of all coloured flowered varieties. In contrast, lipase activity was increased in rats which received Dylan testa diets. It is suggested that the presence of field bean tannins stimulates an increased pancreatic secretion of all digestive enzymes; but in the gut, the affinity of tannin for lipase is less than for either dietary protein or the other digestive enzymes.
Abstract Volume. De artamento de Tecnologia de 10s Alimentos Universidad Politecnica de PI alencia. 46071 Valencia. Spain. AOAC. 1960 Official Methods of Analysis
- Anonymous Neukom
Anonymous. 1987. II International Carob Symposium. Abstract Volume. De artamento de Tecnologia de 10s Alimentos. Universidad Politecnica de PI alencia. 46071 Valencia. Spain. AOAC. 1960. " Official Methods of Analysis, " 13th ed. Association of Of-ficial Analytical Chemist, Washington, DC. Arrigoni, E., Caprez, A., Amado, R., and Neukom, H. 1964. Gravimetric method for the determination of insoluble and soluble dietary fibres. 2. Lebensm. Unters. Forsh. 178: 195.
The Biochemistry of Plants Academic Press Distribution of D-galactosyl groups in guaran and locust bean gum New method for quanti-tative determination of uranic acids
- C W Baker
- R L Whistler
In " The Biochemistry of Plants, " J. Preiss (Ed.). Academic Press, New York. Baker, C.W. and Whistler, R.L. 1975. Distribution of D-galactosyl groups in guaran and locust bean gum. Carbohydr. Res. 45: 237. Blumenkrantz, X. and Asboe-Hansen, G. 1973. New method for quanti-tative determination of uranic acids. Anal. Biochem. 54: 484.
Some pro erties of locust bean gum Natural Plant Hydrocolloids, " p. 51. In l ustrml & Engineering Chem-istry (Ed) Simplified method for the measure-ment of total non-starch polysaccharides by as-liquid chromatography of constituent sugars as alditol acetates
- H Deuel
- H Neukom
Deuel, H. and Neukom, H. 1954. Some pro erties of locust bean gum. In " Natural Plant Hydrocolloids, " p. 51. In l ustrml & Engineering Chem-istry (Ed). American Chemical Society. Washington, DC. Englyst, H. and Cummings, J. 1984. Simplified method for the measure-ment of total non-starch polysaccharides by as-liquid chromatography of constituent sugars as alditol acetates. Arm yst f 109: 937.
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II International Carob Symposium. Abstract Volume. Departamento de Tecnologia de los Alimentos
- Anonymous