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The article describes the recent data dealing with the fatty acid content in cow, goat, and sheep milk. A large body of evidence demonstrates that fatty acid profile in goat and sheep milk was similar to that of cow milk. Palmitic acid was the most abundant in milk. Goat milk had the highest C6:0, C8:0, and C10:0 content. Sheep milk was the richest source of conjugated linoleic acid and α-linolenic acid. Ewe’s milk had lower value of n-6/n-3 then goat and cow milk.
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Bull Vet Inst Pulawy 57, 135-139, 2013
DOI: 10.2478/bvip-2013-0026
FATTY ACID PROFILE OF MILK - A REVIEW
MARIA MARKIEWICZ-KĘSZYCKA, GRAŻYNA CZYŻAK-RUNOWSKA1,
PAULINA LIPIŃSKA, AND JACEK WÓJTOWSKI1
Department of Animal Sciences,
Institute of Genetics and Animal Breeding of the Polish Academy of Sciences,
05-552 Jastrzębiec, Poland
1 Department of Small Mammals Breeding and Raw Materials of Animal Origin,
Poznan University of Life Sciences, 62-002 Suchy Las, Poland
maria.kesz@gmail.com
Received: December 12, 2012 Accepted: May 4, 2013
Abstract
The article describes the recent data dealing with the fatty acid content in cow, goat, and sheep milk. A large body of
evidence demonstrates that fatty acid profile in goat and sheep milk was similar to that of cow milk. Palmitic acid was the most
abundant in milk. Goat milk had the highest C6:0, C8:0, and C10:0 content. Sheep milk was the richest source of conjugated linoleic
acid and α-linolenic acid. Ewe’s milk had lower value of n-6/n-3 then goat and cow milk.
Key words: ruminants, milk, fatty acids, human diet.
Milk and milk products are well balanced
nutritious food in human diet. The premium nutritional
quality of dairy products is highly correlated with milk
fat quality and concerns: high concentration of fat
soluble vitamins and n-3 fatty acids, as well as high
content of conjugated linoleic acid (CLA). Moreover,
milk fat influences processing of raw material and is a
carrier of taste and aroma. The proportion of fat in cow’s
milk is typical - 3.3%-4.4% (14, 32, 33). Goat’s and
ewe’s milk contains approx. 3.25%-4.2% and 7.1% of
fat, respectively (6, 12, 13, 35). The concentration of fat
in milk depends on factors such as: breed, nutrition,
individual traits, and period of lactation.
The purpose of the paper is to review the
specific characteristics of fatty acid profile of cow, goat,
and sheep milk with an emphasis on health benefits for
human organism, as well as milk fat modification
methods enhancing content of unsaturated fatty acids in
raw material.
Cardiovascular disease, cancer, obesity, and
diabetes are collectively responsible for more than 80%
of the disease-related mortality in the United States (2).
Lipids play a critical role in all of these diseases, and the
relative amounts and types of dietary lipids consumed
are believed to be of a critical importance.
Polyunsaturated fatty acids. Until now, it was
believed that due to a lack of appropriate enzymes
mammals may not synthesise de novo two
polyunsaturated fatty acids: α-linolenic acid (ALA) from
the n-3 family and linoleic acid (LA) from the n-6
family, thus they were labelled essential fatty acids
(EFA). Nowadays, it has been found that the term EFA
applied solely to ALA and LA is inadequate (7). It was
discovered that ALA and LA may be formed in the
human organism from hexadecatrienoic acid C16:3 and
hexadecadienoic acid C16:2 (7). Moreover, most of the
effects of EFAs result from their transformation into
eicosanoids.
Human diet in developed countries is
characterised by a too low proportion of n-3 fatty acids
and too high content of n-6 fatty acids. LA and ALA
compete for the same enzymatic systems. Long chain
polyunsaturated fatty acids (LCPUFA) from n-3 family -
eicosapentaenoic acid (EPA) and docosahexaenoic acid
(DHA) may be supplied to the organism with food or
synthesised in the organism from ALA. It was observed
that in the human organism up to 8% of the ALA in
phospholipids may be converted to EPA but only about
8% of dietary ALA was incorporated into phospholipids
(10). Nevertheless, the synthesis of DHA from ALA is
highly limited and is more efficient in infants (about
1%) than in adults (3). Moreover, this process may still
be further hindered by a high consumption of linoleic
acid, which traps an enzyme, δ-6-desaturase, and
prevents further elongation of ALA (19).
DHA is an n-3 fatty acid that constitutes the
main structural component of the brain cinerea, retina,
and semen. DHA has important functions in the
development of premature babies and little children. It
participates actively in the development of the nervous
system, in the process of vision, and in preventing
inflammations. In the elderly, it supports prevention and
treatment of senile dementia. DHA requirement rapidly
136
increases in the last trimester of intrauterine life, at the
time of extremely accelerated brain development (11).
The ratio of n-6/n-3 fatty acids in the diet of
most people ranges from 15:1 to 16.7:1 (28). However,
it is recommended to maintain a markedly lower
proportion of n-6 fatty acids. According to Simopoulos
(28), an optimal n-6/n-3 fatty acids ratio is specific to
different diseases. In the diet of asthmatics it should be
5:1, while in case of patients suffering from rheumatoid
arthritis and colon cancer the author recommended the
n-6/n-3 ratio of 2.5:1 (28). The World Health
Organisation and Food and Agriculture Organisation
Expert Committee recommended the n-6/n-3 fatty acids
ratio to be below 4 since at such a proportion a
considerable (70%) reduction in the number of deaths
caused by cardiovascular diseases was observed (25,
28).
Results of clinical studies indicate that
increased share of n-3 fatty acids in the diet supports
prevention and treatment of cancers, heart diseases,
thrombosis, arterial hypertension, hyperlipidaemia,
senile dementia, Alzheimer’s disease, depression, or
rheumatoid arthritis (19). Moreover, n-3 fatty acids are
used in the treatment of skin diseases, e.g. psoriasis,
acne, and lupus erythematosus.
Fish and seafood are primary sources of EPA
and DHA from the n-3 family. Most vegetables and
fruits contain LA and ALA at the 1:1 ratio, while in
maize grain, soybeans, sunflower seeds, and certain nuts
LA predominates. However, its most important sources
include animal origin products, first of all meat, milk,
and eggs.
Milk fat is one of the most complex natural fats
that consist of approximately 400-500 fatty acids (1).
Milk fat biosynthesis is a complex process, which
requires coordinated control of many cellular processes
and metabolic pathways that occur at various stages of
development and functioning of the mammary gland
(15, 29). Polyunsaturated fatty acids consumed by
ruminants are microbially dehydrogenated in the rumen.
In cow, sheep, and goat, milk EPA and DHA are found
in trace amounts. In cow, goat, and sheep, milk PUFAs
account for as little as ~3% of all fatty acids (8);
however, Strzałkowska et al. (34) and Mayer and
Fiechter (18) found more than 4% of PUFA in goat
milk, and Cieślak et al. (6) found even more than 21%
of PUFAs in milk of sheep fed rapeseeds.
The predominant n-3 FA in milk fat of the
majority of mammals is α-linolenic acid. Milk of sheep
and goats usually has a smaller value of n-6/n-3 ratio
and greater concentration of ALA compared to cows
milk (Table 1).
Monounsaturated fatty acids. Monounsatu-
rated fatty acids do not cause accumulation of
cholesterol as saturated fats do, and do not turn rancid as
readily as polyunsaturated fatty acids. Moreover, they
have a positive effect on the concentration of high
density lipoproteins (HDL), transporting cholesterol
from blood vessel walls to the liver, where it is degraded
by bile acids, which are afterwards excreted from the
organism. At the same time, monounsaturated fats
reduce the concentration of low density lipoproteins
(LDL), which when circulating over the entire organism
are deposited in blood vessels.
The share of monounsaturated fatty acids
(MUFA) is similar in sheep, cow, and goat milk fat and
may range from about 20% to about 35%. Among the
MUFA group, the oleic acid (C18:1) is characterised by
the highest content, which is typical for milk of the
majority of mammals (5, 18, 22, 27, 34, 36). Cow’s milk
is the richest source of oleic acid (24%), while its
content in goat and sheep milk is on average 18% of all
fatty acids (27, 36); however, some authors reported its
higher concentration (more than 20% of all fatty acids)
in sheep and goat milk (18). In ruminant’s milk, there
are also relatively small but significant contributions
from other MUFA such as 14:1 (about 1%), 16:1 (about
1.5%), and very desirable vaccenic acid, which is a
precursor of CLA in human organism (1.5%-5%).
Saturated fatty acids. Although a high
proportion of MUFA and long-chain unsaturated fatty
acids from the n-3 family has an advantageous effect on
human health, saturated fatty acids (SFA) constitute the
primary fat component of human diet. They are stable
substances, originating mainly from animal products. An
excessively high share of SFA in the diet may cause
chronic diseases such as atherosclerosis, heart failure, or
obesity. General dietary recommendations concerning
the reduction of SFA and cholesterol consumption have
contributed to an erroneous belief that dairy products,
particularly full-fat, may lead to coronary heart disease
(9).
The studies conducted since 2000 have
contradicted the thesis that the consumption of milk and
dairy products would increase the synthesis of LDL and
the risk of coronary disease (24). At present, it is
believed that the increased LDL blood concentration is
attributable to lauric C12:0, myristic C14:0, and palmitic
C16:0 acids, while the other saturated fatty acids found
in milk neutralise their effect since they increase HDL
level (24).
Taking into account a negative role of the
C12:0, C14:0, and C16:0 acids, Ulbricht and Southgate
(39) proposed atherogenic indices (AI) and
thrombogenic indices (TI). Based on AI and TI values
conclusions may be drawn concerning fat quality from
the point of view of human diet. The results for AI and
TI for goat, sheep, and cow milk are similar and depend
on breed, stage of lactation, and diet; however, the
lowest values of these indices were for sheep milk,
which is favourable in a health perspective (Table 1).
The values of AI and TI of ruminant milk can be
improved by the administration of either olive cake,
rapeseed oil, linseed oil, or camelina sativa cake to the
diet (6, 36).
Saturated fatty acids in ruminant milk account
for 60% to 70% of fatty acids. The main SFA in milk fat
of the majority of mammals is C16:0. The fat present in
sheep and goat milk is a rich source of medium-chain
fatty acids. In goat milk, these are: C6:0, C8:0, and
C10:0 fatty acids in particular (12, 18, 27, 34).
137
Table 1
Fatty acids profile in goat, sheep, and cow milk
Fatty acids (g 100g -1)
Goat
Sheep
Cow
C4:0; butyric
2.03 1
2.57 2
2.87 3
C6:0; caproic
2.78 1
1.87 2
2.01 3
C8:0; caprylic
2.92 1
1.87 2
1.39 3
C10:0; capric
9.59 1
6.63 2
3.03 3
C12:0; lauric
4.52 1
3.99 2
3.64 3
C14:0; myristic
9.83 1
10.17 2
10.92 3
C16:0; palmitic
24.64 1
25.1 2
28.7 3
C18:0; stearic
8.87 1
8.85 2
11.23 3
18:1cis-9; oleic
18.65 1
20.18 2
22.36 3
18:2 cis-9, cis-12; linoleic
2.25 1
2.32 2
2.57 3
18:2 cis-9, trans-11; CLA
0.45 1
0.76 2
0.57 3
18:3 cis- 9, cis-12, cis- 15 ; α-linolenic
0.77 1
0.92 2
0.5 3
total n-6
1.78 4
2.97 5
2.836
total n-3
0.44 4
1.31 5
0.56 6
SFA
68.79 4
64.23 5
68.72 6
MUFA
24.48 4
29.75 5
27.40 6
PUFA
3.70 4
4.82 5
4.05 6
n-6/n-3
5.00 4
2.31 5
6.01 6
AI
2.88 4
2.21 5
2.55 6
TI
3.17 4
2.49 5
3.22 6
Total fat (g 100g -1)
4.27 1
6.09 2
3.76 3
SFA - saturated fatty acids; MUFA - monounsaturated fatty acids; PUFA - polyunsaturated fatty acids; AI-
atherogenic index; TI - trombogenic index.
Calculated as (39): AI = (C12:0 + (4*C14:0) + C16:0)/(MUFA + (n-6) + (n-3)); TI=(C14:0 + C 16:0 +
C18:0)/(0.5*MUFA + (0.5*n-6) + (3*n-3) + (n-3/n-6)).
1Average value (16, 18, 27, 34), 2average value (16, 18, 36), 3average value (8, 20, 22), 4average value (8, 38),
5average value (8, 36), 6average value (5, 8, 20)
The share of the acids in the pool of FA
composing the goat milk fat is more than twice as high
as in cow’s milk (Table 1). A characteristic trait
distinguishing goat milk from cow and sheep milk is the
relation between lauric C12:0 and capric C10:0 acid
(less than 0.5 and more than 1 in cow milk). It is an
important indicator, as it may be used to detect
falsifications of goat milk with cow’s milk (34). A
higher concentration of C6:0, C8:0, and C10:0 fatty
acids in sheep and goat milk in comparison to cow’s
milk cause a specific aroma in milk of these little
ruminants (34, 38). Furthermore, these fatty acids may
have health-promoting effects on human health by
inhibiting bacterial and viral growth, as well as
dissolving cholesterol deposits.
Trans fatty acids. Fatty acids posing the
greatest threat for human health are partly hydrogenated
vegetable oils, being components of refined oils and
margarines, which contain high amounts of trans
isomers. Approximately 80% all trans fatty acids (TFAs)
in human diet originate from food produced under
commercial scale production conditions, while 20%
come from milk and meat of ruminants (17). TFAs
coming from these food sources considerably differ in
their position isomerism. In individuals, consuming high
amounts of partly hydrogenated vegetable oils there is a
dependence between the incidence of coronary disease
and TFA consumption, while such a dependence has not
been observed in case of dairy products (30). The main
TFAs in ruminant milk are conjugated linoleic acid and
vaccenic acid.
Conjugated linoleic acid. In the last twenty
years, CLA has been of a considerable interest of
researchers. CLAs are conjugated dienes of linoleic acid.
This name refers to a group of position and geometric
isomers of linoleic acid, characterised by a conjugated
system of double bonds, separated by one single bond.
There are 28 potential CLA isomers of which rumenic
acid (C18:2 cis-9, trans-11) is dominant in milk fat.
Studies on animals indicate that CLA exhibits
immunostimulatory, antihypertensive, anticarcinogenic,
and antiatherogenic properties and promotes a reduction
of body weight (21, 37).
The effect of CLA on the human organism has
been verified by a limited number of studies and their
results are not conclusive. Mougios et al. (21) observed
a reduction of skin fold thickness and percentage
contents of adipose tissue in the organisms of
individuals consuming 1.4 g CLA/day. In these studies,
a trend was also recorded for a decrease in serum lipid
content; although only the disadvantageous decrease in
HDL level was statistically significant. Most research
reports indicate a necessity to exercise caution while
applying CLA. The advantageous effect of CLA as a
138
factor correcting the serum lipid profile, body weight, or
the metabolism of insulin and glucose among patients
with diabetes type II, has not been confirmed in most
cases. Investigations conducted by Tricon et al. (37) on
the effect of CLA-enriched dairy products by a
modification of diet for milk-producing animals did not
confirm their health-promoting effect.
The sheep and goat milk are usually richer in
CLA than cow’s milk, probably due to the semi-
extensive nature of the system under which little
ruminants are usually farmed (40). Several studies have
found higher concentration of CLA in milk fat of ewes
than of goats. Some authors observed the CLA
concentration in ewe’s milk as high as 2.2% of FA (16).
Usually, under the same dietary treatment, sheep milk
has higher CLA content than goat milk, what can be
explained by the differences found in mRNA of their
mammary adipocytes (40).
Milk fat improvement. Despite the fact that it
is difficult to enrich ruminant’s milk with PUFA by
changing the feed ration, still many authors observed
advantageous changes in the fatty acid profile in milk of
cows, ewes, and goats consuming feed rations rich in
green forages (5, 17). Several authors have found that
organic milk has higher MUFA, PUFA, and CLA
contents, and as a result they are healthier and have
higher nutritional value than conventional ones (5, 23,
38). However, according to O’Donnell-Megaro et al.
(23) the above difference is not enough to affect public
health.
Stoop et al. (31) found that there is a
considerable genetic variation for fatty acid
composition, with genetic variation being high for C4:0
to C16:0 and moderate for C18 fatty acids. The
moderate coefficient of variation in combination with
moderate to high heritability indicates that fatty acid
composition can be changed by genetic selection (31).
Schennink et al. (26) found that the DGAT1 K232A
polymorphism has a clear influence on milk fat
composition. The DGAT1 allele that encodes lysine (K)
at position 232 (232K) is associated with more saturated
fat; a larger fraction of C16:0, smaller fractions of
C14:0, unsaturated C18:3, and conjugated linoleic acid.
In a whole genome association analysis, Bouwman et al.
(4) found a total of 54 regions that were significantly
associated with one of more fatty acids. Medium chain
and unsaturated fatty acids are strongly influenced by
polymorphisms in DGAT1 and SCD1. Other regions also
showed significant associations with the fatty acids
studied. This information helps in unraveling the genetic
background of milk fat composition.
Supplementation of feed rations for ruminants
with fish oils, vegetable oils, oilseeds, and other forms
of protected fats may also, to a certain degree, influence
an increase in the content of unsaturated fatty acids in
milk (20, 27), but some authors reported their negative
effect on milk flavour. Moreover, it can cause milk fat
depression and decrease in milk yield. The change of
fatty acid composition of milk can also alter the
rheological properties of milk products i.e. a
considerably softer butter. Nevertheless, in most studies,
supplementing dairy cows, ewes, and goats with
vegetable oils or oilseeds improved milk fat
composition. Milk was characterised by increased levels
of beneficial nutritional factors, including MUFA and n-
3 PUFA, and also by lower AI and TI (6, 12, 36).
The review presented the most recent data
concerning fatty acid composition in cow, ewe, and goat
milk. While there are a lot of data for FA profile of
cow’s milk, this area needs further investigations on
goat and ewe’s milk because of large differences in fatty
acid profile among breeds within these species.
Moreover, rapidly growing market for functional food
and recent findings in the physiological effects of
nutritionally desirable fatty acids, that are present in
milk, have generated the need of improved knowledge
on health-promoting effects of dairy products on human
organism, and on possibilities of improvement of milk
fat composition throughout various factors, such as
feeding regime, production system, breed, or stage of
lactation.
Acknowledgments: The authors acknow-
ledge the financial support of the Project ‘Biofood –
innovative, functional animal products’,
no.POIG.01.01.02-014-090/09 co-financed by the
European Union from the European Regional
Development Fund within the Innovative Economy
Operational Programme 2007-2013.
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... Milk is one of the most complex fat matrices and the fatty acid profile includes monounsaturated fatty acids (MUFAs) (25%), followed by polyunsaturated fatty acids (PUFAs) in smaller quantity (2.3%). The low proportion of PUFAs is explained by the fact that ruminants do not synthesize them "de novo" and their presence in milk is strongly correlated to dietary PUFAs and the amount absorbed in the intestine [3][4][5]. Because of this rich composition of unsaturated fatty acids, milk is the subject of several processes that can be involved in changing of its composition. ...
... Only SFAs values were strongly negatively correlated with all other parameters (except for the Ω6/Ω3 ratio) proving an inverse proportionality between those classes of compounds and oxidation products. 3 polyunsaturated fatty acids, 4 omega 3 fatty acids, 5 omega 6 fatty acids, 6 ratio between omega 6 and omega 3 fatty acids, 7 absorbance read at 450 nm, 8 absorbance read at 495 nm, 9 absorbance read at 532 nm, 10 malondialdehyde concentration expressed as μg/L. ...
... The absorption values recorded at 450 nm and 495 nm (wavelengths specific for MUFAs degradation products) indicated higher MUFAs concentrations for sheep milk compared to cow milk, an observation also sustained by another study [24]. Sheep milk, with important concentrations of unsaturated fatty acids, is assumed to be healthier than cow milk [3], but the susceptibility to peroxidation has to be considered. ...
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Having a complex fatty acid profile, milk is the subject of several oxidation processes that are different to those in other food matrices. Considering this, is important to appreciate the degradation status of milk using rapid and simple methods to quantify the main degradation products. The aim of this study was to adapt a simple and rapid method for determination of milk oxidative stability and to quantify malondialdehyde, one of the lipid oxidation products. Four parameters (trichloroacetic acid concentration—TCA, antioxidant type, incubation time, and thiobarbituric acid—TBA concentration) were modified to establish the best experimental sequence. It was concluded that the relevant results were obtained by precipitating milk proteins using 20% TCA; incubating samples for 90 min with 0.8% TBA, without adding antioxidant; and registering absorbance at three different wavelengths (450, 495, and 532 nm). This method was successfully applied to cow and sheep milk samples and the absorbance values obtained provided information about degradation of fatty acids for both milk types. The Pearson correlation showed a positive relationship between the fatty acid profiles of milk samples and the absorbance values that characterized their oxidation pattern during storage.
... Along with butyric (C4:0), caproic (C6:0), and caprylic acid (C8:0), capric acid (C10:0) was also found and its content was comparable in the analyzed fat samples, with the greatest amount noted in the fat extracted from sour cream samples enriched with 100% lemon peel and juniper berry essential oils and with 50% and 100% clove bud essential oils. The presence of C6:0, C8:0, and C10:0 fatty acids in ruminant milk may cause a specific aroma in milk and may exert beneficial effects on human health by inhibiting bacterial and viral growth, as well as by dissolving cholesterol deposits [66]. ...
... Due to its unique structure, it inhibits the enzymes involved in the deposition of adipose tissue. It also reduces the synthesis of adipose tissue, intensifies lipolysis, and has been proven to exhibit anticancer, antidiabetic, anti-inflammatory, and anti-atherosclerotic properties [66,67]. In our study, the content of CLA in the extracted fat samples varied within narrow limits (0.85-0.93%), regardless of the type of fat studied. ...
Article
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Essential oils derived from plant materials are a mixture of compounds that exhibit antibacterial properties. Due to their distinct aroma, they also serve as a desirable natural additive for various food products, including dairy products. In this study, the essential oils of lemon peels, clove buds, and juniper berries were obtained by steam distillation and characterized using gas chromatography–mass spectrometry to determine their chemical compositions and effects on the viability of seven Bifidobacterium strains. Furthermore, the effect of essential oils on the viability of Bifidobacterium animalis subsp. lactis Bb-12 was investigated in cream samples during fermentation and after storage for 21 days at 6 °C. The fatty acid composition of fat extracted from essential oils containing sour cream samples and the volatile aroma compound profile of the sour cream samples were also determined chromatographically. Among the 120 compounds identified, monoterpene hydrocarbons were dominant in the essential oils of lemon peels (limonene and γ-terpinene) and juniper berries (sabinene and β-myrcene), while eugenol and eugenol acetate were abundant in the essential oil of clove buds. In addition to these compounds, butanoic and acetic acids were found in the tested sour cream samples. In turn, fat extracted from these samples was rich in saturated fatty acids, mainly palmitic acid. Among the tested strains of the genus Bifidobacterium, B. animalis subsp. lactis Bb-12 was the most sensitive to the essential oils of clove and juniper, as indicated by the larger growth inhibition zones. However, both the concentration and type of essential oils used had no effect on the number of cells of this strain present in the cream samples immediately after fermentation and after its 21-day storage, which suggests that the tested essential oils could be a natural additive to dairy products.
... The scientific literature generically shows in some cases the use of protein materials as binders in protective and aesthetic treatments on the surface of the stone [10,15,18,28]. In more specific cases, the use of sheep or cow's milk has been better hypothesized; the origin of milk can sometimes be identified by the content of short-and medium-chain fatty acids and the ratio of lauric acid to capric acid (C12:0/C10:0) [29,30]. The value of the C12:0/C10:0 ratio of 0.35 measured in sample 22 [26,27] and the presence in the infrared spectrum of the peak still identifiable at 1734 cm −1 [10] could be associated with the use of sheep's milk. ...
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The protection of the stone surfaces of the buildings of the city of Lecce (Apulia, Italy) represents an ancient practice, which has always allowed the conservation of the historical-artistic heritage of the city, which nowadays is an international touristic and cultural destination. The identification of ancient recipes, materials and methodologies for the protection of historical buildings plays an important role in establishing correct protocols in order to ensure the durability of stone surfaces over time. This work presents a historically accurate reconstruction of the materials and conservation technologies used on the facades of the artistic buildings in Lecce. Several historical buildings, both civil and religious, have been selected in order to investigate the treatments applied on their facades and to know the traditions spread in the past in the field of building conservation in the Salento territory. Thanks to non-invasive or micro-destructive techniques (optical microscopy, ATR-FTIR spectroscopy, pyrolysis–gas chromatography–mass spectrometry), the characteristic molecular markers of the materials and the products of degradation have been identified, deepening the knowledge of the mechanisms of deterioration and interaction between the stone material, the surface finish and the surrounding environment. The paper is a valuable tool for the knowledge of ancient traditions and the planning of proper restoration works.
... Unsaturated trans FAs have their double bonds in the trans configuration. With the usual configuration of unsaturated FAs being cis; trans FAs are formed either naturally via metabolic processes like microbial activity in ruminant animals or industrially by hydrogenation (Markiewicz-Keszycka et al., 2013;Calder, 2015). Each cis unsaturated FA can give multiple trans isomers, but the major ones include elaidic acid (trans C18:1 n−9), TVA (trans C18:1 n−11), and CLA (c9 t11 C18:2 and c12 t10 C18:2) (Calder, 2015). ...
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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.
... Regarding the content of functional substances, such as bioactive lipids, scientific studies have recognized the benefits of the consumption of certain fatty acids; butyric acid (C4) has been recognized for its antitumor effect on prostate, breast, and colon; caproic (C6), caprylic (C8), and capric (C10) acids have been associated with the inhibition of microbial and viral growth and dissolution of cholesterol deposits in in vitro tests and in experimental animals. Conjugated linoleic acid (CLA) has been reported to have anticancer and antiteratogenic properties and has even been associated with weight loss, although the data obtained come from studies in cell cultures and experimental animals [6,7]. In a study of organic milk from ten commercial brands offered in the north of England, the contents of short-, medium-, and long-chain, saturated and unsaturated fatty acids were recorded. ...
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The study of milk fat composition is a priority topic at the international level; however, there are few studies on the composition of triacylglycerides (TAG) and sterols in cow’s milk produced in organic production systems. The objective of this study was to determine the profile of TAG, cholesterol, and other sterols in the fat of raw cow’s milk produced under organic conditions in the municipality of Tecpatán, Chiapas. Every month for one year, milk samples were obtained from three production units (PU 1, 2 and 3) and from the collecting tank (CT) of the municipality (12 months × 4 = 48 samples), in accordance with Mexican regulations. Milk fat was extracted by detergent solution and TAG and sterol analyses were performed by gas chromatography with a flame ionization detector and capillary columns. Chromatographic analyses identified and quantified 15 TAG in all milk fats, from C26 to C54, with a bimodal behavior; the maximum value (% w/w) for the first mode was located at C38 (14.48) and, for the second mode, C50 and C52 were considered with values of 11.55 and 11.60, respectively. Analysis of variance (ANOVA) followed by Tukey’s test only yielded significance (p < 0.05) for C26; most TAG values over time showed homogeneous variability. Cholesterol, brassicasterol, and campesterol were also determined; ANOVA did not show statistical significance (p ≥ 0.05) between them in the production units and collecting tank. Cholesterol had the highest percentage of the sterols with a mean value of 96.41%. The TAG and cholesterol profiles found in this study were similar to those reported in other countries.
... This gives goat milk special therapeutic properties in certain aspects of human nutrient metabolism [1,20,21]. However, C12:0, C14:0, and C16:0 increase the levels of low-density lipoprotein (LDL) in the blood, which is detrimental to the health of the body [22,23]. ...
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Malonyl/acetyltransferase (MAT) is a crucial functional domain of fatty acid synthase (FASN), which plays a vital role in the de novo synthesis of fatty acids in vivo. Milk fatty acids are secreted by mammary epithelial cells. Mammary epithelial cells are the units of mammary gland development and function, and it is a common model for the study of mammary gland tissue development and lactation. This study aimed to investigate the effects of MAT deletion on the synthesis of triacylglycerol and medium-chain fatty acids. The MAT domain was knocked out by CRISPR/Cas9 in the goat mammary epithelial cells (GMECs), and in MAT knockout GMECs, the mRNA level of FASN was decreased by approximately 91.19% and the protein level decreased by 51.83%. The results showed that MAT deletion downregulated the contents of triacylglycerol and medium-chain fatty acids (p < 0.05) and increased the content of acetyl-Coenzyme A (acetyl-CoA) (p < 0.001). Explicit deletion of MAT resulted in significant drop of FASN, which resulted in downregulation of LPL, GPAM, DGAT2, PLIN2, XDH, ATGL, LXRα, and PPARγ genes in GMECs (p < 0.05). Meanwhile, mRNA expression levels of ACC, FASN, DGAT2, SREBP1, and LXRα decreased following treatment with acetyl-CoA (p < 0.05). Our data reveals that FASN plays critical roles in the synthesis of medium-chain fatty acids and triacylglycerol in GMECs.
... Furthermore, linolenic fatty acid (FA) (C18 : 3 (n-3)) and linoleic FA (C18 : 2 (n-6)) are the most abundant omega 3 (n-3) and omega 6 (n-6) FA in milk, respectively, both considered essential FA [17]. Moreover, the n-6/n-3 ratio (recommended to be below 4/1) is considered an indicator for nutritional impact of milk fat on human health [18][19][20]. Therefore, due to the great consumer demand for dairy products, milk composition modification in favor of healthy FA and against SFA and trans FA continues to be a challenge [13]. ...
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This study is aimed at comparing the milk fatty acid profile (FAP) of cows that changed from a mixed system (MS) of double grazing plus total mixed ration (TMR) to a total confinement system (TCS, 100% TMR) with cows that changed to another MS with one overnight grazing plus TMR and compare with cows that were kept unchanged in TCS. The diet change was made in the second month of lactation. The milk samples were collected at one (M1-spring) and three months of lactation (M3-summer). Three treatments are as follows (each n = 10 ): confined cows fed with TMR throughout the period (GTMR), cows that changed from MS with double grazing plus TMR in M1 to TCS in M3 (GCHD), and cows that changed from a MS with double grazing plus TMR in M1 to a MS with overnight grazing plus TMR in M3 (GTMR+P). Unlike GTMR+P, GCHD improved milk production after change (increased 14% from M1 to M3), but milk FAP was impaired. In M3, conjugated linoleic acid (C18 : 2-CLA) in GTMR and GCHD was lower than GTMR+P ( p < 0.05 ), and linolenic (C18 : 3-n-3) was lower in GCHD than GTMR+P. Maintaining grazing in summer overnight sustained milk fat quality, evidenced by higher C18 : 3 (n-3); C18 : 2 (CLA); and n-6/n-3 ratio than cows that changed to TCS.
... Caprylic acid is one medium-chain fatty acid which easy to absorb than long-chain fatty acid [18]. The level of caprylic acid on milk is around 1.39 g 100 g -1 of total milk fat; caprylic acid is also classified as easy to evaporate [19]-caprylic acid milk fat produced by the endogenous and exogenous process. The endogenous process occurs by elongating short-chain fatty acid [20], while the exogenous process is affected by the feeding system. ...
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Milking time is one of the factors that affect milk quality. The objective of this study was to differentiate morning milk from afternoon based on milk fatty acid profile and create a prediction model using Near-Infrared Reflectance Spectroscopy (NIRS). This study used explorative research and post-observation analysis. Milk sampling was collected from three different dairy farm locations in West Java Provinces (Pangalengan district of Bandung Regency, Cibungbulang District of Bogor Regency, and Tanah Sareal District of Bogor Municipality). Milk quality observed in this study included milk fat, protein, lactose, solid non-fat (SNF), and fatty acid compositions. Milk fat, protein, lactose, and SNF were analyzed using Lactoscan. Fatty acid compositions were identified using gas chromatography (GC). Sample spectrums were collected using NIRSflex 500. The difference between morning and afternoon milking was tested using a t-test carried out by SPSS ver. 25. Qualitative calibration of milk quality was conducted using NIRSCal v5.6 by applying the cluster (CLU) method. The results from lactoscan and GC showed that milk fat, caprylic acid, and myristoleic acid, and total SFA were significantly different (Sig. (2-tailed) < 0.05) in morning and afternoon milk. However, NIRS failed to generate a sophisticated model for the milk quality differentiation, which shows a low Q-value (0.0011231). The quantitative analysis accurately produced milk fat and total SFA predictions but failed to accurately predict caprylic acid and myristoleic acid. This study concluded that morning milk could be differentiated from afternoon milk based on milk fat, caprylic acid, myristoleic acid, and total SFA content. The NIRS technology can differentiate between morning and afternoon milk based on quantitative calibration of total fat and SFA.
Chapter
This chapter highlights the potential health benefits of camel milk including antioxidant, anti-cancer activity, antihypertensive properties, antidiabetic activity, antimicrobial activity, hypoallergenicity activity , and anti-Crohn's disease. In addition to the most recent identified functional properties of camel milk. The bioactivity of conjugated linoleic acid (CLA), D and L amino acid, as well as oligosaccharide in camel milk will be also discussed. The proposed mechanisms behind these properties and potential health benefits are explained. This chapter also describes composition and nutritive value of camel milk and their association to functional properties. The current available information in the literature on camel milk is covered too.
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The popularity of plant-based milk has been increasing over the last few years to substitute animal milk. Cereal such as black rice ( Oryza sativa L.) is a plant material that can be used to produce rice milk. Black rice has been reported to have high vitamin and mineral content and high fiber. Previous research also has shown the functionality of black rice, such as antioxidant, antihypertensive, and antihyperlipidemic. For this reason, black rice has the potency to be further processed into functional food such as rice milk. However, there is still a lack of basic information about the nutritional profile of black rice milk. Therefore, this research aimed to examine the fatty acids and amino acids profile of black rice milk. Fatty acid analysis was carried out using GC-FID. Amino acid content was analyzed using UPLC. The fatty acid profile analysis revealed that polyunsaturated fatty acid was the most abundant (0.1062%) in black rice milk, followed by saturated fatty acid (0.062%). The highest amino acid found in black rice milk was glutamic acid (0.0045 g/100 mL), aspartic acid (0.00269 g/100 mL), and arginine (0.0228 g/100 mL)
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The study aimed at determining the concentration of free fatty acids (FFA) and some chemical and physical traits of goat milk as related to the stage of lactation, age and somatic cell count (SCC). Used were 60 Polish White Improved goats. Diets were formulated according to the INRA standards and met all the individual nutritive requirements of goats. Milk samples were taken every month throughout the whole lactation. The highest level of FFA and fat content of milk was recorded in the last stage of lactation, in primiparous does and in milk with lowest SCC. However, in general, because the goats were free from sub- and clinical mastitis their milk was characterized by low level of FFA (<1.0 mEq/L), Thus, milk obtained from goats with healthy mammary glands was characterized by low susceptibility to lipolysis.
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Free radicals are natural final products of the intensive metabolism in cells located in organism high-yielding dairy cows. When the disturbing of homeostasis occurs, oxidative processes lead to oxidative stress which in high-yielding dairy cows cause inflammation of the mammary gland (mastitis). The inflammation can cause the reduction of milk yield and unfavourable changes in the milk composition, e.g. reduction in fat, casein proteins and calcium content with a simultaneous increase in the concentration of whey proteins, sodium and chlorine. Moreover, the activity of enzymes such a lipases, proteases, peroxides and the plasminogen in milk increases, negatively affecting its technological properties. In dairy cows the oxidative stress is associated with retaining placenta after calving and disrupting the activity of the corpus luteum, what affect the reproductive functions. The active immune response to inflammation leads to an increase in the secretion of other molecules having an adverse effect on embryo survival.
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Investigated were changes in selected redox parameters - vitamin C, malondialdehyde (MDA) and glutathione (GSH) content of goat blood plasma - as markers of oxidative stress after per os administration the N-acetylcysteine (NAC). Used were 20 Polish White Improved goats, selected from the fock of 60 animals. Within the selected goats distinguished were four groups according to somatic cell counts (SCC) of milk: group I - below 1×106, group II - 1×106-2×106, group III - 2×106-4×106 and group IV - above 4×106/ml. Concentrations of GSH, MDA and vitamin C of blood plasma were assessed just at start of the experiment and then after 7 days of daily administration of 12 mg NAC per kg body weight to goats. After 7 days of administering NAC to goats the plasma concentration of both MDA and GSH dropped and that of vitamin C increased. It is concluded that NAC administered per os increases the anti-oxidant capacity and may reduce the content of lipid peroxidation products in blood plasma of milking goats.
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Interest in the development of dairy products naturally enriched in conjugated linoleic acid (CLA) exists. However, feeding regimens that enhance the CLA content of milk also increase concentrations of trans-18:1 fatty acids. The implications for human health are not yet known. This study investigated the effects of consuming dairy products naturally enriched in cis-9,trans-11 CLA (and trans-11 18:1) on the blood lipid profile, the atherogenicity of LDL, and markers of inflammation and insulin resistance in healthy middle-aged men. Healthy middle-aged men (n = 32) consumed ultra-heat-treated milk, butter, and cheese that provided 0.151 g/d (control) or 1.421 g/d (modified) cis-9,trans-11 CLA for 6 wk. This was followed by a 7-wk washout and a crossover to the other treatment. Consumption of dairy products enriched with cis-9,trans-11 CLA and trans-11 18:1 did not significantly affect body weight, inflammatory markers, insulin, glucose, triacylglycerols, or total, LDL, and HDL cholesterol but resulted in a small increase in the ratio of LDL to HDL cholesterol. The modified dairy products changed LDL fatty acid composition but had no significant effect on LDL particle size or the susceptibility of LDL to oxidation. Overall, increased consumption of full-fat dairy products and naturally derived trans fatty acids did not cause significant changes in cardiovascular disease risk variables, as may be expected on the basis of current health recommendations. Dairy products naturally enriched with cis-9,trans-11 CLA and trans-11 18:1 do not appear to have a significant effect on the blood lipid profile.
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Despite the fact that cholesterol is a comparatively stable component of cows' milk its concentration is, within a certain range, subject to significant variation related to the season (probably the feeding system), lactation stage and somatic cell count in milk. The highest differences (about 25%) in the amount of cholesterol per g milk fat were observed between the first and last lactation stage. Despite the decreasing milk yield with the progress of lactation, the amount of cholesterol secreted with milk increased significantly. In the milk of cows for which the somatic cell count was below 100 thousand/ml the cholesterol content was by about 10% lower than that in milk characterized by a higher somatic cell count. The positive correlation coefficients obtained between the amount of cholesterol expressed as mg/100 ml milk and the per cent of fat and protein indicate that selection conducted for increasing the concentration of nutritive components in milk will result in an increased cholesterol content. However, the quantity of cholesterol per 1 g milk fat will decrease. There was observed no correlation between the content of cholesterol in milk and the polymorphic forms of LGB.
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The aim of the study was to evaluate the effect of milk yield and stage of lactation on the activity of liver enzymes, cholesterol, and vitamin C concentration in blood of milking cows. The experiment was carried out on Polish Holstein-Friesian Black and White dairy cows with two different milk yield levels: M - medium (about 7000 kg per lactation) and H - high (about 10 000 kg per lactation). In blood serum, AST, ALT, GGT, CHOL, and vitamin C were estimated. The AST and ALT activities in the blood serum were lower in M group than in H group, however within M and H groups there were no differences in both aminotransferases activity between the 60th and the 200th day of lactation. Differences in GGT activity (P ≤ 0.01), CHOL (P ≤ 0.05), and vitamin C level (P ≤ 0.01) in blood serum were found between both stages of lactation. Negative correlations between vitamin C level with somatic cell count and milk yield traits were observed, that may indicate an increase in oxidative processes in high-yielding dairy cows. The achieved results may be used in diagnostics and/or evaluation of herds from the point of view of biochemical and pathophysiological processes.
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The aim of the study was to determine the effect of the type of silage (wilted grass vs. whole maize plants) offered to high-yielding dairy cows on cholesterol content of their milk. Silage type did not affect the cholesterol level as expressed either in mg/100 ml milk or as mg/g milk fat. However, the significant relationships were identified between the cholesterol content of milk and stage of lactation, milk somatic cell count, daily milk yield, fat content of milk and the amount of fat yielded daily.
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Processes of milk fat biosynthesis and milk fat globules secretion are gaining increasing attention in recent years. Milk fat not only provides calories and nutritionally important components, but also greatly contributes to the organoleptic characteristics of dairy products. Milk fat globules are formed and secreted from mammary epithelial cells. The functioning and development of the mammary gland is a very complex process. The changes in hormonal levels upon each pregnancy cause the mammary epithelial cells to proliferate, differentiate and die due to apoptosis. The paper brings together current information regarding the regulation of the mammary gland development, regulation of milk fat synthesis, as well as characterizes key stages in the biosynthesis, formation and secretion of milk fat globules.
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Fat is the most differentiated milk constituent. It occurs in the form of natural emulsion, i.e. dispersed fat globules of average diameter 0.1-20 μm. It is composed of triglycerides that account for 96-99% of total milk fat, phospholipids, sterols, including cholesterol, free fatty acids and fat-soluble vitamins A, D, E, K as well as beta-carotene. Milk fat consists of approximately 400-500 fatty acids that are divided into numerous groups, subject to chain length and a saturation degree. Among fatty acids, there are those with negative effects to consumers' health, such as an increased blood cholesterol level. The saturated fatty acids include lauric (C12:0) and myristic acids (C14:0), while the unsaturated ones are those of trans configuration. Palmitic acid (C16:0) was shown to induce occasional negative effects in elderly people, whereas stearic acid (C18:0) remains neutral in this respect. However, milk fat comprises a considerable number of health-beneficial fatty acids, such as butyric acid (C4:0), oleic acid (C18:0) and polyunsaturated ones, like linoleic acid (C18:2), a-linolenic acid (C18:3), arachidonic acid (C20:4), eicosapentaenoic acid (C20:5), docosahexaenoic acid (C22:6) and CLA (isomer cis 9 trans 11).
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Physico-chemical characteristics of sheep and goat milk in Austria as influenced by seasonal effects and regional differences were investigated. Considerable seasonal variations were observed regarding most constituents. Sheep milk from three different dairy plants showed very similar chemical composition and physical properties, whereas average means of sheep milk were significantly different from goat milk except for freezing point, pH, and a few fatty acids (C12:0, C18:0, C18:1). The mean values obtained for sheep and goat milk during the whole season were: pH 6.59/6.59, freezing point −0.544/−0.542 °C, ash 0.853/0.813%, total solids 15.78/11.70%, crude protein 5.21/3.15%, casein 3.98/2.39%, whey protein 0.92/0.52%, urea 0.432/0.335 g L−1, fat 5.75/3.74%, lactose 4.64/4.32%, citric acid 1.535/1.018 g L−1, phosphorus 1.454/1.009 g L−1, chloride 1.196/1.755 g L−1, sodium 0.442/0.317 g L−1, potassium 1.248/2.015 g L−1, calcium 1.846/1.288 g L−1, magnesium 0.192/0.138 g L−1, orotic acid 17.02/12.09 mg kg−1,and cholesterol 11.6/9.8 mg 100 g−1 milk, respectively.