Has the association between saturated fatty acids, serum cholesterol and coronary heart disease been over emphasized?

Influence of supplemental choline on milk yield, fatty acid profile, and weight changes in postpartum ewes and their offspring

Background and Aim

The most intensive nutritional requirements occur during milk production's peak. Ewe milk contains more protein and fat than cow milk. The nutritional factors significantly determine the composition. The liver undergoes high stress during lactation but is relieved by essential nutrients. Choline acts metabolically as a lipotrope. This compound functions in cell structure construction, maintenance, and acetylcholine synthesis. The animal nutrition industry provides choline from various sources, such as synthetic and natural kinds. This study evaluated the influence of two distinct choline sources on dairy ewes' peripartum and postpartum milk production, composition, and offspring growth.

Materials and Methods

Twenty-four Rambouillet ewes, each weighing around 63.7 ± 1.7 kg, aged three with two previous births, spent 30-day pre-partum and post-partum in individual pens (2 × 2 m). They were given different experimental treatments 30 days before and after birth according to a randomized design; no choline (a), 4 g/day rumen-protected choline (RPC) (b), or 4 g/day thiocholine (c). Milk samples for milk composition and long-chain fatty acid (FA) analysis were taken every 30 days during milk collection.

Results

Significant differences (p < 0.05) in ewe body weight, lamb birth weight, and 30-day-old lamb body weight were observed at lambing and on day 30 of lactation due to choline treatment. Milk yield was significantly higher (1.57 kg/day) compared to the control (1.02 kg/day) and RPC (1.39 kg/day), due to the herbal choline source. There was no significant difference in the milk's protein, lactose, fat, non-fat solids, and total milk solids content between the treatments. Herbal choline lowers (p < 0.05) the concentrations of caproic, caprylic, capric, lauric, and myristic acids while boosting (p < 0.05) those of oleic and cis-11-eicosenoic acid, the changes influencing long-chain FA levels (p < 0.05).

Conclusion

Providing choline from both sources to ewes enhanced milk production and body weight at lambing and on 30-day post-lambing. The herbal choline supplement altered short-chain milk FAs, while representative concentration pathways affected medium-chain ones.

Emerging Parameters Justifying a Revised Quality Concept for Cow Milk

Milk has become a staple food product globally. Traditionally, milk quality assessment has been primarily focused on hygiene and composition to ensure its safety for consumption and processing. However, in recent years, the concept of milk quality has expanded to encompass a broader range of factors. Consumers now also consider animal welfare, environmental impact, and the presence of additional beneficial components in milk when assessing its quality. This shifting consumer demand has led to increased attention on the overall production and sourcing practices of milk. Reflecting on this trend, this review critically explores such novel quality parameters, offering insights into how such practices meet the modern consumer's holistic expectations. The multifaceted aspects of milk quality are examined, revealing the intertwined relationship between milk safety, compositional integrity, and the additional health benefits provided by milk's bioactive properties. By embracing sustainable farming practices, dairy farmers and processors are encouraged not only to fulfill but to anticipate consumer standards for premium milk quality. This comprehensive approach to milk quality underscores the necessity of adapting dairy production to address the evolving nutritional landscape and consumption patterns.

Valorization of Prunus Seed Oils: Fatty Acids Composition and Oxidative Stability

Prunus fruit seeds are one of the main types of agri-food waste generated worldwide during the processing of fruits to produce jams, juices and preserves. To valorize this by-product, the aim of this work was the nutritional analysis of peach, apricot, plum and cherry seeds using the official AOAC methods, together with the extraction and characterization of the lipid profile of seed oils using GC-FID, as well as the measurement of the antioxidant activity and oxidative stability using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging method. Chemometric tools were required for data evaluation and the obtained results indicated that the main component of seeds were oils (30-38%, w). All seed oils were rich in oleic (C18:1n9c) and linoleic (C18:2n6c) acids and presented heart-healthy lipid indexes. Oil antioxidant activity was estimated in the range IC50 = 20-35 mg·mL-1, and high oxidative stability was observed for all evaluated oils during 1-22 storage days, with the plum seed oil being the most antioxidant and stable over time. Oxidative stability was also positively correlated with oleic acid content and negatively correlated with linoleic acid content. Therefore, this research showed that the four Prunus seed oils present interesting healthy characteristics for their use and potential application in the cosmetic and nutraceutical industries.

Microbiome-driven breeding strategy potentially improves beef fatty acid profile benefiting human health and reduces methane emissions

BACKGROUND

Healthier ruminant products can be achieved by adequate manipulation of the rumen microbiota to increase the flux of beneficial fatty acids reaching host tissues. Genomic selection to modify the microbiome function provides a permanent and accumulative solution, which may have also favourable consequences in other traits of interest (e.g. methane emissions). Possibly due to a lack of data, this strategy has never been explored.

RESULTS

This study provides a comprehensive identification of ruminal microbial mechanisms under host genomic influence that directly or indirectly affect the content of unsaturated fatty acids in beef associated with human dietary health benefits C18:3n-3, C20:5n-3, C22:5n-3, C22:6n-3 or cis-9, trans-11 C18:2 and trans-11 C18:1 in relation to hypercholesterolemic saturated fatty acids C12:0, C14:0 and C16:0, referred to as N3 and CLA indices. We first identified that ~27.6% (1002/3633) of the functional core additive log-ratio transformed microbial gene abundances (alr-MG) in the rumen were at least moderately host-genomically influenced (HGFC). Of these, 372 alr-MG were host-genomically correlated with the N3 index (n=290), CLA index (n=66) or with both (n=16), indicating that the HGFC influence on beef fatty acid composition is much more complex than the direct regulation of microbial lipolysis and biohydrogenation of dietary lipids and that N3 index variation is more strongly subjected to variations in the HGFC than CLA. Of these 372 alr-MG, 110 were correlated with the N3 and/or CLA index in the same direction, suggesting the opportunity for enhancement of both indices simultaneously through a microbiome-driven breeding strategy. These microbial genes were involved in microbial protein synthesis (aroF and serA), carbohydrate metabolism and transport (galT, msmX), lipopolysaccharide biosynthesis (kdsA, lpxD, lpxB), or flagellar synthesis (flgB, fliN) in certain genera within the Proteobacteria phyla (e.g. Serratia, Aeromonas). A microbiome-driven breeding strategy based on these microbial mechanisms as sole information criteria resulted in a positive selection response for both indices (1.36±0.24 and 0.79±0.21 sd of N3 and CLA indices, at 2.06 selection intensity). When evaluating the impact of our microbiome-driven breeding strategy to increase N3 and CLA indices on the environmental trait methane emissions (g/kg of dry matter intake), we obtained a correlated mitigation response of -0.41±0.12 sd.

CONCLUSION

This research provides insight on the possibility of using the ruminal functional microbiome as information for host genomic selection, which could simultaneously improve several microbiome-driven traits of interest, in this study exemplified with meat quality traits and methane emissions. Video Abstract.

Lipophilic Compounds and Antibacterial Activity of Opuntia ficus-indica Root Extracts from Algeria

The chemical composition, investigated by gas chromatography-mass spectrometry, and antibacterial activity of lipophilic extractives of three varieties of Opuntia ficus-indica roots from Algeria are reported in this paper for the first time. The results obtained revealed a total of 55 compounds, including fatty acids, sterols, monoglycerides and long chain aliphatic alcohols that were identified and quantified. β-Sitosterol was found as the major compound of the roots of the three varieties. Furthermore, considerable amounts of essential fatty acids (ω3, ω6, and ω9) such as oleic, linoleic, and linolenic acids were also identified. The green variety was the richest among the three studied varieties. The antibacterial activity, evaluated with disc diffusion method, revealed that lipophilic extracts were effective mainly against Gram-positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) (19~23 mm). Gram-negative strains mainly Pseudomonas aeruginosa gave an inhibition zone of 18 mm, which is considered high antibacterial activity. The minimal inhibitory concentrations of the tested bacteria revealed interesting values against the majority of bacteria tested: 75–100 µg mL⁻¹ for Bacillus sp., 250–350 µg/mL for the two Staphylococcus strains, 550–600 µg mL⁻¹ for E. coli, and 750–950 µg mL⁻¹ obtained with Pseudomonas sp. This study allows us to conclude that the lipophilic fractions of cactus roots possess interesting phytochemicals such as steroids, some fatty acids and long chain alcohols that acted as antibiotic-like compounds countering pathogenic strains.

Effect of cow’s milk with different PUFA n-6: n-3 ratios on performance, serum lipid profile, and blood parameters of grower gilts

The concern with human health has increased the interest in producing foods enriched with polyunsaturated fatty acids (PUFA), directly or naturally, by inclusion in the animals’ diet. The positive effects such as antithrombotic, anti-inflammatory, and hypolipidemic have been observed in pigs and rats, used as human models for study. The present study evaluated the effect of cow’s milk with different lipid profiles on performance, serum fatty acid profile, biochemical analysis, and a complete blood count of gilts used as a human model. At 34 days, thirty gilts were equally distributed in three treatments. Experimental treatments were milk from cows without the oil supplementation (C), milk from cows fed an enriched diet with linseed oil (n-3), and milk from cows fed an enriched diet with soybean oil (n-6). Milk supplementation was performed until 190 days old, provided once in the morning. The n-3 and n-6 milk reduced the concentration of myristic acid in the blood and increased the leukocytes. Milk enriched with n-3 compared to n-6 reduced the stearic acid. In conclusion, milk with a better PUFA profile can reduce saturated fatty acids in the blood and alter the concentration of cells in the defense system.

Malonyl/Acetyltransferase (MAT) Knockout Decreases Triacylglycerol and Medium-Chain Fatty Acid Contents in Goat Mammary Epithelial Cells

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.

Chemical Composition, Fatty Acid Profile, and Lipid Quality Indices in Commercial Ripening of Cow Cheeses from Different Seasons

The aim of the study was to compare and demonstrate whether commercial rennet ripening cheeses available on the market in summer and winter differ in their chemical composition, fatty acid profile, content of cis9trans11 C18:2 (CLA) acid and other trans isomers of C18:1 and C18:2 acid and whether they are characterized by different values of lipid quality assessment indices. The experimental material consisted of rennet ripening of cheeses produced from cow's milk available in the Polish market. The first batch contained cheeses produced in winter and purchased from the market between May and June. The second batch contained cheeses produced in summer and purchased between November and December. Chemical composition was analyzed by FoodScan apparatus. The gas chromatography (GC) method was used to determine the content of fatty acids. Results obtained in the presented study indicate that the chemical composition, content of fatty acids trans isomers, and lipid quality indices varied between summer and winter cheeses. The summer cheeses were richer sources of MUFA and PUFA compared to winter cheeses. Summer cheeses were also characterized by lower content of SFA, higher content n - 3, lower n - 6/n - 3 ratio, and higher content of DFA. Higher contents of CLA and trans C18:1 and C18:2 were found in summer cheeses.

Survey on fatty acid profiles of retail pasteurised cow’s milk and cow’s yogurt in Bulgaria

Assessing the consumer’s awareness of the diet-health relationship, this study presents the fatty acid composition of cow’s milk available on Bulgarian market. Over a 5-year period, 100 samples of pasteurised cow’s milk and 135 samples cow’s yogurt were analysed by gas chromatography (ISO 15885:2002). The saturated fatty acids predominated - average amount 70.1% for milk and 71.1% for yogurt. The unsaturated fatty acids proportions were 29.9% and 28.9% respectively. Seasonal variations in the fatty acid composition of milk were detected, due to feeding practices. Non-milk fat was identified in 5 yogurt samples, while all pasteurised milk samples were not adulterated. This study provides the first scientific information for fatty acid composition of cow’s milk on Bulgarian market with respect to dietary intake estimation.

A Comprehensive Review of the Composition, Nutritional Value, and Functional Properties of Camel Milk Fat

Recently, camel milk (CM) has been considered as a health-promoting icon due to its medicinal and nutritional benefits. CM fat globule membrane has numerous health-promoting properties, such as anti-adhesion and anti-bacterial properties, which are suitable for people who are allergic to cow's milk. CM contains milk fat globules with a small size, which accounts for their rapid digestion. Moreover, it also comprises lower amounts of cholesterol and saturated fatty acids concurrent with higher levels of essential fatty acids than cow milk, with an improved lipid profile manifested by reducing cholesterol levels in the blood. In addition, it is rich in phospholipids, especially plasmalogens and sphingomyelin, suggesting that CM fat may meet the daily nutritional requirements of adults and infants. Thus, CM and its dairy products have become more attractive for consumers. In view of this, we performed a comprehensive review of CM fat's composition and nutritional properties. The overall goal is to increase knowledge related to CM fat characteristics and modify its unfavorable perception. Future studies are expected to be directed toward a better understanding of CM fat, which appears to be promising in the design and formulation of new products with significant health-promoting benefits.

Effect of Dietary Supplementation with Lipids of Different Unsaturation Degree on Feed Efficiency and Milk Fatty Acid Profile in Dairy Sheep

Lipids of different unsaturation degree were added to dairy ewe diet to test the hypothesis that unsaturated oils would modulate milk fatty acid (FA) profile without impairing or even improving feed efficiency. To this aim, we examined milk FA profile and efficiency metrics (feed conversion ratio (FCR), energy conversion ratio (ECR), residual feed intake (RFI), and residual energy intake (REI)) in 40 lactating ewes fed a diet with no lipid supplementation (Control) or supplemented with 3 fats rich in saturated, monounsaturated and polyunsaturated FA (i.e., purified palmitic acid (PA), olive oil (OO), and soybean oil (SBO)). Compared with PA, addition of OO decreased milk medium-chain saturated FA and improved the concentration of potentially health-promoting FA, such as cis-9 18:1, trans-11 18:1, cis-9 trans-11 CLA, and 4:0, with no impact on feed efficiency metrics. Nevertheless, FA analysis and decreases in FCR and ECR suggested that SBO supplementation would be a better nutritional strategy to further improve milk FA profile and feed efficiency in dairy ewes. The paradox of differences observed depending on the metric used to estimate feed efficiency (i.e., the lack of variation in RFI and REI vs. changes in FCR and ECR) does not allow solid conclusions to be drawn in this regard.

The Comparison of Fatty Acid Composition and Lipid Quality Indices in Hard Cow, Sheep, and Goat Cheeses

This study aimed to evaluate the fatty acid composition, including the contents, of conjugated linoleic acid cis9trans11 C18:2 (CLA) and trans C18:1 and C18:2 isomers in hard cow, sheep, and goat cheeses found on the Polish market and to compare lipid quality indices in these cheeses. The gas chromatography method was used to determine the fatty acid profile. The study demonstrated various contents of cis9trans 11 C18:2 (CLA), trans C18:1, and C18:2 isomers and the values of lipid quality indices in the cheeses. Sheep and goat cheeses were richer sources of short-chain fatty acids (SCFA) (14.73 ± 2.55% and 14.80 ± 2.80%, respectively) than the cow cheeses (9.38 ± 0.87%). The cow cheeses had a significantly higher (p < 0.05) content of monounsaturated fatty acids (MUFA), the lowest n-6/n-3 ratio, and the highest content of fatty acids, inducing a desirable dietary effect in humans (DFA) compared to the sheep and goat cheeses. Significantly higher (p < 0.05) contents of polyunsaturated fatty acids (PUFA) were found in sheep cheeses. Goat cheeses had the highest n-3 PUFA content and the lowest values of the thrombogenicity index (TI) (2.67 ± 0.44) compared to the sheep and cow cheeses (3.14 ± 0.29 and 3.13 ± 0.13, respectively). The cow, sheep, and goat cheeses were characterized by similar values of the hypocholesterolemic/hypercholesterolemic (H/H) ratio. Sheep cheeses had the highest levels of cis9trans11 C18:2 (CLA) and the highest total content of trans C18:1 and trans C18:2 isomers. The research showed that sheep, cow, and goat cheeses offered various health benefits. The differences in fatty acid composition and the different values of the lipid quality indices found in the cheeses may be due to differences in both the composition of milk used to produce them and the cheese-making technology. Studies conducted by many authors have indicated that the feeding system of the ruminants has a significant impact on the quality and chemical composition of milk, as well as its applicability for cheese production.

Fatty acid profile and nutrient composition of muscle and adipose tissue from Malpura and fat-tailed Dumba sheep

Fatty acid (FA) profile and nutrient composition of Longissimus dorsi (LD) muscle and various adipose tissues of adult Malpura sheep (4–6 years) and lambs (6 month), and fat tailed Dumba sheep (1 year) were evaluated. Compared to lamb, LD muscle of adult Malpura sheep had lower polyunsaturated FA (PUFA), ω-6, ω-6/ω-3, desirable FA (DFA) and higher atherogenic index (AI), monounsaturated FA (MUFA), ω-3, MUFA:PUFA ratio, short-chain FA (SCFA) and conjugated linoleic acid (CLA). Similarly, adipose tissue fat had higher MUFA, MUFA:PUFA ratio and AI in adult than the lamb. Dumba sheep showed a different FA profile with higher SFA in caul fat and lower in LD muscle, while proportionally lower PUFA in caul fat and higher in LD muscle. Likewise, ω-3 and ω-6 FA was comparatively more in LD muscle while c911 CLA was highest in the tail adipose tissue. Between Malpura and Dumba, the FA profile of LD muscle revealed higher SFA and cis-9 trans-11 CLA but lower PUFA and ω-6 FA in Malpura. It can thus be concluded that Malpura lamb meat is healthier having improved PUFA,ω-6:ω-3 ratio and AI than the adult. Furthermore, Dumba may also be considered a promising mutton breed with significant PUFA, ω-3 and ω-6 FA. Further studies are needed to ascertain the effects of different dietary regime on the FA profile of Dumba and Malpura sheep.

Dietary saturated fat and heart disease: a narrative review

The American Heart Association (AHA) recently published a meta-analysis that confirmed their 60-year-old recommendation to limit saturated fat (SFA, saturated fatty acid) and replace it with polyunsaturated fat to reduce the risk of heart disease based on the strength of 4 Core Trials. To assess the evidence for this recommendation, meta-analyses on the effect of SFA consumption on heart disease outcomes were reviewed. Nineteen meta-analyses addressing this topic were identified: 9 observational studies and 10 randomized controlled trials. Meta-analyses of observational studies found no association between SFA intake and heart disease, while meta-analyses of randomized controlled trials were inconsistent but tended to show a lack of an association. The inconsistency seems to have been mediated by the differing clinical trials included. For example, the AHA meta-analysis only included 4 trials (the Core Trials), and those trials contained design and methodological flaws and did not meet all the predefined inclusion criteria. The AHA stance regarding the strength of the evidence for the recommendation to limit SFAs for heart disease prevention may be overstated and in need of reevaluation.

Effects of agroindustrial by-product supplementation on dairy goat milk characteristics, nutrient utilization, ruminal fermentation, and methane production

The use of agroindustrial by-products, such as dried distillers grains with solubles (DDGS) and dried citrus pulp (DCP), has been widely investigated in dairy cows, but information on their effects in dairy goats is limited. The influence of feeding olive cake (a by-product of olive oil production) to dairy goats has been assessed in some studies, but exhausted olive cake (EOC) has been much less investigated. Twelve Murciano-Granadina goats were used in a crossover design trial with 2 periods to assess the effects of including agroindustrial by-products on nutrient digestibility, ruminal fermentation, methane production, urinary excretion of purine derivatives, and milk yield and composition. In each period, 6 goats received daily a control diet comprising 1 kg of alfalfa hay and 1 kg of high-cereal concentrate, and another 6 goats received a diet (BYP) comprising 1 kg of alfalfa hay and 1 kg of a concentrate including corn DDGS, DCP, and EOC in proportions of 180, 180, and 80 g/kg of concentrate (as-fed basis), respectively. Diet had no effect on total dry matter intake, but intake of alfalfa hay, CP, and fat was greater for the BYP group than for the control group. There were no differences between diets in nutrient apparent digestibility, with the exception of fat, which was greater for the BYP diet compared with the control diet. Although fecal N tended to be greater for the BYP diet, there were no differences in N utilization. Compared with the control diet, milk yield tended to be greater and daily production of milk CP, fat, whey protein, and TS as well as milk gross energy were greater for the BYP diet. The concentration of C12:0, C14:0, and C16:0 fatty acids (FA) was or tended to be lower and the concentration of polyunsaturated FA was greater in the milk of BYP-fed goats compared with goats fed the control diet. Diet had no effect on ruminal parameters (pH, volatile FA, and NH₃-N concentrations) and methane emissions, but urinary excretion of total purine derivatives tended to be lower in BYP-fed goats than in those fed the control diet. A mixture of corn DDGS (180 g), DCP (180 g), and EOC (80 g) could replace 44% of cereal grains and protein feeds in the concentrate for dairy goats without compromising nutrient utilization, ruminal fermentation, or milk yield and led to a more unsaturated FA profile in milk.

The health-nutrition dimension: a methodological approach to assess the nutritional sustainability of typical agro-food products and the Mediterranean diet

BACKGROUND

The aim of this paper is to provide a methodological approach to evaluate the nutritional sustainability of typical agro-food products, representing Mediterranean eating habits and included in the Mediterranean food pyramid.

RESULTS

For each group of foods, suitable and easily measurable indicators were identified. Two macro-indicators were used to assess the nutritional sustainability of each product. The first macro-indicator, called 'business distinctiveness', takes into account the application of different regulations and standards regarding quality, safety and traceability as well as the origin of raw materials. The second macro-indicator, called 'nutritional quality', assesses product nutritional quality taking into account the contents of key compounds including micronutrients and bioactive phytochemicals. For each indicator a 0-10 scoring system was set up, with scores from 0 (unsustainable) to 10 (very sustainable), with 5 as a sustainability benchmark value. The benchmark value is the value from which a product can be considered sustainable. A simple formula was developed to produce a sustainability index.

CONCLUSION

The proposed sustainability index could be considered a useful tool to describe both the qualitative and quantitative value of micronutrients and bioactive phytochemical present in foodstuffs. This methodological approach can also be applied beyond the Mediterranean, to food products in other world regions. © 2018 Society of Chemical Industry.

Role of Fatty Acids in Milk Fat and the Influence of Selected Factors on Their Variability-A Review

Fatty acids (FAs) of milk fat are considered to be important nutritional components of the diets of a significant portion of the human population and substantially affect human health. With regard to dairy farming, the FA profile is also seen as an important factor in the technological quality of raw milk. In this sense, making targeted modifications to the FA profile has the potential to significantly contribute to the production of dairy products with higher added value. Thus, FAs also have economic importance. Current developments in analytical methods and their increasing efficiency enable the study of FA profiles not only for scientific purposes but also in terms of practical technological applications. It is important to study the sources of variability of FAs in milk, which include population genetics, type of farming, and targeted animal nutrition. It is equally important to study the health and technological impacts of FAs. This review summarizes current knowledge in the field regarding sources of FA variability, including the impact of factors such as: animal nutrition, seasonal feed changes, type of animal farming (conventional and organic), genetic parameters (influence of breed), animal individuality, lactation, and milk yield. Potential practical applications (to improve food technology and consumer health) of FA profile information are also reviewed.

Milk fat components with potential anticancer activity-a review

During many years, the milk fat has been unfairly undervalued due to its association with higher levels of cardiovascular diseases, dyslipidaemia or obesity, among others. However, currently, this relationship is being re-evaluated because some of the dairy lipid components have been attributed potential health benefits. Due to this, and based on the increasing incidence of cancer in our society, this review work aims to discuss the state of the art concerning scientific evidence of milk lipid components and reported anticancer properties. Results from the in vitro and in vivo experiments suggest that specific fatty acids (FA) (as butyric acid and conjugated linoleic acid (CLA), among others), phospholipids and sphingolipids from milk globule membrane are potential anticarcinogenic agents. However, their mechanism of action remains still unclear due to limited and inconsistent findings in human studies.

Effect of substituting soybean meal and canola cake with dried distillers grains with solubles at 2 dietary crude protein levels on feed intake, milk production, and milk quality in dairy cows

Dried distillers grain with solubles (DDGS) is an alternative source of feed protein for dairy cows. Previous studies found that DDGS, based on grains other than corn, can substitute for soybean meal and canola cake as a dietary protein source without reducing milk production or quality. As societal concerns exist, and in many areas strict regulation, regarding nitrogen excretion from dairy cows, the dairy industry has focused on reducing dietary protein level and nitrogen excretion. In the present study, we investigated the use of DDGS as a protein source, at a marginally low dietary crude protein (CP) levels, in a grass-clover and corn silage-based ration. The experiment involved 24 Holstein cows and 2 protein sources (DDGS or soybean-canola mixture) fed at 2 levels of CP (14 or 16%) in a 4 × 4 Latin square design. The aim of this study was to evaluate the effect of both protein source and protein level on feed intake, milk yield, and milk quality. The results indicated that feed intake, milk yield, and protein in milk increased when the protein level in the ration was 16% CP compared with 14%. We found no effect of substituting the soybean-canola mixture with DDGS. Moreover, no sensory problems were observed when comparing fresh milk with stored milk, and milk taste was unaffected by DDGS. Milk from cows fed DDGS had a slightly higher content of linoleic acid and conjugated linoleic acid (CLA 9-11), and lower content of C11 to C17 fatty acids than cows fed diets with the soybean-canola mixture. Cows fed the diets with 16% CP produced milk with higher oleic acids and lower palmitic acid content than cows fed 14% CP diets. To conclude, DDGS can substitute for a soybean-canola mixture without affecting feed intake, milk yield and quality, or sensory quality. Under the conditions of this experiment, feeding 16% CP compared with 14% CP in the ration can increase feed intake and milk production.

Dairy food products: good or bad for cardiometabolic disease?

Prevalence of type 2 diabetes mellitus (T2DM) is rapidly increasingly and is a key risk for CVD development, now recognised as the leading cause of death globally. Dietary strategies to reduce CVD development include reduction of saturated fat intake. Milk and dairy products are the largest contributors to dietary saturated fats in the UK and reduced consumption is often recommended as a strategy for risk reduction. However, overall evidence from prospective cohort studies does not confirm a detrimental association between dairy product consumption and CVD risk. The present review critically evaluates the current evidence on the association between milk and dairy products and risk of CVD, T2DM and the metabolic syndrome (collectively, cardiometabolic disease). The effects of total and individual dairy foods on cardiometabolic risk factors and new information on the effects of the food matrix on reducing fat digestion are also reviewed. It is concluded that a policy to lower SFA intake by reducing dairy food consumption to reduce cardiometabolic disease risk is likely to have limited or possibly negative effects. There remain many uncertainties, including differential effects of different dairy products and those of differing fat content. Focused and suitably designed and powered studies are needed to provide clearer evidence not only of the mechanisms involved, but how they may be beneficially influenced during milk production and processing.

Higher PUFA and n-3 PUFA, conjugated linoleic acid, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: a systematic literature review and meta- and redundancy analyses

Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of organic production standards affects milk quality. Here we report results of meta-analyses based on 170 published studies comparing the nutrient content of organic and conventional bovine milk. There were no significant differences in total SFA and MUFA concentrations between organic and conventional milk. However, concentrations of total PUFA and n-3 PUFA were significantly higher in organic milk, by an estimated 7 (95 % CI -1, 15) % and 56 (95 % CI 38, 74) %, respectively. Concentrations of α-linolenic acid (ALA), very long-chain n-3 fatty acids (EPA+DPA+DHA) and conjugated linoleic acid were also significantly higher in organic milk, by an 69 (95 % CI 53, 84) %, 57 (95 % CI 27, 87) % and 41 (95 % CI 14, 68) %, respectively. As there were no significant differences in total n-6 PUFA and linoleic acid (LA) concentrations, the n-6:n-3 and LA:ALA ratios were lower in organic milk, by an estimated 71 (95 % CI -122, -20) % and 93 (95 % CI -116, -70) %. It is concluded that organic bovine milk has a more desirable fatty acid composition than conventional milk. Meta-analyses also showed that organic milk has significantly higher α-tocopherol and Fe, but lower I and Se concentrations. Redundancy analysis of data from a large cross-European milk quality survey indicates that the higher grazing/conserved forage intakes in organic systems were the main reason for milk composition differences.

Composition differences between organic and conventional meat: a systematic literature review and meta-analysis

Demand for organic meat is partially driven by consumer perceptions that organic foods are more nutritious than non-organic foods. However, there have been no systematic reviews comparing specifically the nutrient content of organic and conventionally produced meat. In this study, we report results of a meta-analysis based on sixty-seven published studies comparing the composition of organic and non-organic meat products. For many nutritionally relevant compounds (e.g. minerals, antioxidants and most individual fatty acids (FA)), the evidence base was too weak for meaningful meta-analyses. However, significant differences in FA profiles were detected when data from all livestock species were pooled. Concentrations of SFA and MUFA were similar or slightly lower, respectively, in organic compared with conventional meat. Larger differences were detected for total PUFA and n-3 PUFA, which were an estimated 23 (95 % CI 11, 35) % and 47 (95 % CI 10, 84) % higher in organic meat, respectively. However, for these and many other composition parameters, for which meta-analyses found significant differences, heterogeneity was high, and this could be explained by differences between animal species/meat types. Evidence from controlled experimental studies indicates that the high grazing/forage-based diets prescribed under organic farming standards may be the main reason for differences in FA profiles. Further studies are required to enable meta-analyses for a wider range of parameters (e.g. antioxidant, vitamin and mineral concentrations) and to improve both precision and consistency of results for FA profiles for all species. Potential impacts of composition differences on human health are discussed.

Postprandial lipid responses do not differ following consumption of butter or vegetable oil when consumed with omega-3 polyunsaturated fatty acids

Dietary saturated fat (SFA) intake has been associated with elevated blood lipid levels and increased risk for the development of chronic diseases. However, some animal studies have demonstrated that dietary SFA may not raise blood lipid levels when the diet is sufficient in omega-3 polyunsaturated fatty acids (n-3PUFA). Therefore, in a randomised cross-over design, we investigated the postprandial effects of feeding meals rich in either SFA (butter) or vegetable oil rich in omega-6 polyunsaturated fatty acids (n-6PUFA), in conjunction with n-3PUFA, on blood lipid profiles [total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and triacylglycerol (TAG)] and n-3PUFA incorporation into plasma lipids over a 6-h period. The incremental area under the curve for plasma cholesterol, LDL-C, HDL-C, TAG and n-3PUFA levels over 6 h was similar in the n-6PUFA compared to SFA group. The postprandial lipemic response to saturated fat is comparable to that of n-6PUFA when consumed with n-3PUFA; however, sex-differences in response to dietary fat type are worthy of further attention.

The antihyperlipidemic effect of Fu-Ling-Pi is associated with abnormal fatty acid metabolism as assessed by UPLC-HDMS-based lipidomics

The surface layer of Poria cocos (SLPC), a traditional Chinese medicine, has been commonly used for diuretic and antihyperlipidemia in Asia.

Interannual and geographical reproducibility of the nutritional quality of milk fat from commercial grazing flocks

The objective of the present work was to study the differences in the fatty acid (FA) composition of raw sheep milk fat under commercial milk production conditions throughout lactation, in two consecutive years. Particular attention was placed on the C18:2cis-9,trans-11 isomer, C18:1trans-11 acid, and unsaturated FA as the feeding regimen of 10 commercial flocks of latxa dairy sheep changed from indoor feeding to part-time grazing conditions (from early spring) as traditionally practiced in the Basque Country (Northern Spain). Farms located at an altitude of between 600 and 700 m, in two different geographical areas with different rainfall were selected. Milk samples were collected monthly from late January (indoor feeding) until mid-, or end of, June (outdoor feeding), during two consecutive years. In spite of some interannual variability (most likely due to large differences in rainfall), the evolution of individual FA throughout lactation was comparable between years, indicating that it was reproducible under commercial milk production conditions. The average concentrations of C18:2cis-9,trans-11 isomer and C18:1trans-11 acid in milk from the commercial flocks increased about 200% during the transition period (end of March or early April until May), from indoor feeding (late January or early February until the end of March) to the outdoor period (early May to mid-June), remaining constant during the outdoor period (27·53 ± 9·32 μmol/g fat and 71·58 ± 20·53 μmol/g fat, respectively). Non-atherogenic FA comprised approximately 50% of all saturated FA at any time during lactation, whereas the milk atherogenicity index decreased significantly during the outdoor period. The Trolox-equivalent antioxidant capacity of the water-soluble milk fraction did not appear to be influenced by feeding management. The FA composition of cheeses made during the second year with milk from the indoor or outdoor periods reflected those of the corresponding milks. A principal components analysis clearly showed that differences in the milk FA composition were primarily due to outdoor grazing, with very little contribution from the geographical zone or the year.

Comparison of native and capric acid-enriched mustard oil effects on oxidative stress and antioxidant protection in rats

The present study evaluated the effect of mustard oil enriched in capric acid, a medium-chain fatty acid, on antioxidant enzyme activities in liver and brain and on the levels of malondialdehyde (MDA) in liver, brain and plasma in rats; the effect of adding cholesterol to the diet was also investigated. Charles Foster male albino rats weighing 80–100 g were fed one of four diets for 30 d (six rats per group). In the absence of added dietary cholesterol, the addition of capric acid to the diet resulted in lower plasma total cholesterol, non-HDL-cholesterol and TAG concentrations, higher HDL-cholesterol concentrations, higher antioxidant enzyme activities in liver and brain and lower MDA concentrations in liver, brain and plasma. Adding cholesterol to the diet increased plasma total cholesterol, non-HDL-cholesterol and TAG concentrations, decreased HDL-cholesterol concentration, decreased the activities of antioxidant enzymes and increased tissue and plasma MDA concentrations. Including capric acid in the diet of rats receiving cholesterol at least partly prevented the effects of the increased cholesterol. It is concluded that compared with native mustard oil, capric acid-enriched mustard oil improves blood lipids, enhances antioxidant protection and reduces lipid peroxidation.

The role of reducing intakes of saturated fat in the prevention of cardiovascular disease: where does the evidence stand in 2010?

Current dietary recommendations advise reducing the intake of saturated fatty acids (SFAs) to reduce coronary heart disease (CHD) risk, but recent findings question the role of SFAs. This expert panel reviewed the evidence and reached the following conclusions: the evidence from epidemiologic, clinical, and mechanistic studies is consistent in finding that the risk of CHD is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs). In populations who consume a Western diet, the replacement of 1% of energy from SFAs with PUFAs lowers LDL cholesterol and is likely to produce a reduction in CHD incidence of ≥2-3%. No clear benefit of substituting carbohydrates for SFAs has been shown, although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index. Insufficient evidence exists to judge the effect on CHD risk of replacing SFAs with MUFAs. No clear association between SFA intake relative to refined carbohydrates and the risk of insulin resistance and diabetes has been shown. The effect of diet on a single biomarker is insufficient evidence to assess CHD risk. The combination of multiple biomarkers and the use of clinical endpoints could help substantiate the effects on CHD. Furthermore, the effect of particular foods on CHD cannot be predicted solely by their content of total SFAs because individual SFAs may have different cardiovascular effects and major SFA food sources contain other constituents that could influence CHD risk. Research is needed to clarify the role of SFAs compared with specific forms of carbohydrates in CHD risk and to compare specific foods with appropriate alternatives.

Survey of the fatty acid composition of retail milk in the United States including regional and seasonal variations

Consumers are increasingly aware that food components have the potential to influence human health maintenance and disease prevention, and dietary fatty acids (FA) have been of special interest. It has been 25 years since the last survey of US milk FA composition, and during this interval substantial changes in dairy rations have occurred, including increased use of total mixed rations and byproduct feeds as well as the routine use of lipid and FA supplements. Furthermore, analytical procedures have improved allowing greater detail in the routine analysis of FA, especially trans FA. Our objective was to survey US milk fat and determine its FA composition. We obtained samples of fluid milk from 56 milk processing plants across the US every 3 mo for one year to capture seasonal and geographical variations. Processing plants were selected based on the criteria that they represented 50% or more of the fluid milk produced in that area. An overall summary of the milk fat analysis indicated that saturated fatty acids comprised 63.7% of total milk FA with palmitic and stearic acids representing the majority (44.1 and 18.3% of total saturated fatty acids, respectively). Unsaturated fatty acids were 33.2% of total milk FA with oleic acid predominating (71.0% of total unsaturated fatty acids). These values are comparable to those of the previous survey in 1984, considering differences in analytical techniques. Trans FA represented 3.2% of total FA, with vaccenic acid being the major trans isomer (46.5% of total trans FA). Cis-9, trans-11 18:2 conjugated linoleic acid represented 0.55% total milk FA, and the major n-3 FA (linolenic acid, 18:3) composed 0.38%. Analyses for seasonal and regional effects indicated statistical differences for some FA, but these were minor from an overall human nutrition perspective as the FA profile for all samples were numerically similar. Overall, the present study provides a valuable database for current FA composition of US fluid milk, and results demonstrate that the milk fatty acid profile is remarkably consistent across geographic regions and seasons from the perspective of human dietary intake of milk fat.

Fat composition of organic and conventional retail milk in northeast England

This study of UK retail milk identified highly significant variations in fat composition. The survey, conducted over 2 yr replicating summer and winter, sampled 22 brands, 10 of which indicated organic production systems. Results corroborate earlier farm-based findings considering fat composition of milk produced under conventional and organic management. Organic milk had higher concentrations of beneficial fatty acids (FA) than conventional milk, including total polyunsaturated fatty acids (PUFA; 39.4 vs. 31.8 g/kg of total FA), conjugated linoleic acid cis-9,trans-11 (CLA9; 7.4 v 5.6 g/kg of FA), and α-linolenic acid (α-LN; 6.9 vs. 4.4 g/kg of FA). As expected, purchase season had a strong effect on fat composition: compared with milk purchased in winter, summer milk had a lower concentration of saturated fatty acids (682 vs. 725 g/kg of FA) and higher concentrations of PUFA (37.6 vs. 32.8 g/kg of FA), CLA9 (8.1 vs. 4.7 g/kg of FA), and α-LN (6.5 vs. 4.6 g/kg of FA). Differences identified between sampling years were more surprising: compared with that in yr 2, milk purchased in year 1 had higher concentrations of PUFA (37.5 vs. 32.9 g/kg of FA), α-LN (6.0 vs. 5.1 g/kg of FA), and linoleic acid (19.9 vs. 17.5 g/kg of FA) and lower concentrations of C16:0 and C14:0 (332 vs. 357 and 110 vs. 118 g/kg of FA, respectively). Strong interactions were identified between management and season as well as between season and year of the study. As in the earlier farm studies, differences in fat composition between systems were greater for summer compared with winter milk. Large between-year differences may be due to changes in weather influencing milk composition through forage availability, quality, and intake. If climate change predictions materialize, both forage and dairy management may have to adapt to maintain current milk quality. Considerable variation existed in milk fat composition between brands.

Survey of the fatty acid composition of retail milk differing in label claims based on production management practices

Consumers are becoming increasingly health conscious, and food product choices have expanded. Choices in the dairy case include fluid milk labeled according to production management practices. Such labeling practices may be misunderstood and perceived by consumers to reflect differences in the quality or nutritional content of milk. Our objective was to investigate nutritional differences in specialty labeled milk, specifically to compare the fatty acid (FA) composition of conventional milk with milk labeled as recombinant bST (rbST)-free or organic. The retail milk samples (n=292) obtained from the 48 contiguous states of the United States represented the consumer supply of pasteurized, homogenized milk of 3 milk types: conventionally produced milk with no specialty labeling, milk labeled rbST-free, and milk labeled organic. We found no statistical differences in the FA composition of conventional and rbST-free milk; however, these 2 groups were statistically different from organic milk for several FA. When measuring FA as a percentage of total FA, organic milk was higher in saturated FA (65.9 vs. 62.8%) and lower in monounsaturated FA (26.8 vs. 29.7%) and polyunsaturated FA (4.3 vs. 4.8%) compared with the average of conventional and rbST-free retail milk samples. Likewise, among bioactive FA compared as a percentage of total FA, organic milk was slightly lower in trans 18:1 FA (2.8 vs. 3.1%) and higher in n-3 FA (0.82 vs. 0.50%) and conjugated linoleic acid (0.70 vs. 0.57%). From a public health perspective, the direction for some of these differences would be considered desirable and for others would be considered undesirable; however, without exception, the magnitudes of the differences in milk FA composition among milk label types were minor and of no physiological importance when considering public health or dietary recommendations. Overall, when data from our analysis of FA composition of conventional milk and milk labeled rbST-free or organic were combined with previous analytical comparisons of the quality and composition of these retail milk samples, results established that there were no meaningful differences that would affect public health and that all milks were similar in nutritional quality and wholesomeness.

Short chain saturated fatty acids decrease circulating cholesterol and increase tissue PUFA content in the rat

This study investigates the effect of various dietary saturated fatty acid (SFA) profiles on plasma lipid parameters and tissue fatty acid composition in rats. The experiment was designed to monitor polyunsaturated fatty acids (PUFA) levels, while examining different amounts and types of SFA. Four isocaloric diets were prepared, containing 10-11 mol% of fatty acids (FA) as linoleic acid (LNA) and 2.5 mol% as α-linolenic acid (ALA), leading to an identical and well-balanced LNA/ALA ratio. The initial rapeseed oil/corn oil mixture providing ALA and LNA was enriched with olive oil to prepare the olive oil diet. The butterfat diet was supplemented with butterfat, containing short-chain SFA (C4:0-C10:0, 17 mol% of FA), lauric acid (C12:0, 3.2 mol%), myristic acid (C14:0, 10.5 mol%) and palmitic acid (C16:0, 14.5 mol%). The saturates diet was supplemented with trilaurin, trimyristin and tripalmitin to obtain the same level of lauric, myristic and palmitic acids as the butterfat diet, without the short-chain SFA. The trimyristin diet was enriched with trimyristin only. The results showed that the butterfat diet contributed to specific effects, compared to the olive oil diet and the saturates and trimyristin diets: a decrease in plasma total, LDL- and HDL-cholesterol, higher tissue storage of ALA and LNA, and a higher level of (n-3) highly unsaturated fatty acids in some tissues. This study supports the hypothesis that in diets with identical well-balanced LNA/ALA ratios, short chain SFA may decrease circulating cholesterol and increase tissue polyunsaturated fatty acid content in the rat.