Total Lipids of Sarda Sheep Meat that Include the Fatty Acid and Alkenyl Composition and the CLA and Trans-18:1 Isomers

Research on meat quality of Qianhua Mutton Merino sheep and Small-tail Han sheep

In this study, we analyzed the meat quality of Qianhua Mutton Merino sheep (QHMM). QHMM and Small-tail Han sheep (STH) were selected as the test animals. After slaughtering, the longissimus dorsi muscles were tested to determine the nutrient composition, content of amino acid, fatty acid, and muscle fiber diameter. According to the nutrient test result, the protein content of QHMM was higher than that of STH. However, the fat content was significantly lower (P < 0.05) than STH. Additionally, total amino acid content, total essential amino acid content, total half-essential amino acid content, total non-essential amino acid content, and flavor amino acid content of QHMM were significantly higher (P < 0.05) than those of STH. Moreover, the contents of C22:1 n9, C18:2 n6, C18:3 n6, C22:6 n6, and C10:0 of the muscle in QHMM were significantly higher (P < 0.05) than those of STH. Furthermore, the essential amino acid score, the total unsaturated-to-saturated fatty acid ratio, and the polyunsaturated-to-saturated fatty acid ratio of QHMM were greater than those of STH. Additionally, the muscle fiber diameter of QHMM was considerably lower (P < 0.01) than that of STH. In conclusion, the meat quality of QHMM was better than that of STH.

Feeding Algae Meal to Feedlot Lambs with Competent Reticular Groove Reflex Increases Omega-3 Fatty Acids in Meat

The aim of this study was to compare the effects of supplementing marine algae as a source of omega-3 fatty acids (FA) in the diet, mixed in the concentrate or bottle-fed, on intramuscular fat FA composition of lambs with competent reticular groove reflex (RGR). Forty-eight feedlot lambs were distributed in three equal groups: one group did not consume marine algae nor had competent RGR, the second group received a daily dose (2.5%) of algae meal in the concentrate and the last group consumed the same dose of algae meal emulsified in milk replacer and bottle-fed. Marine algae raised the contents of EPA, DPA, and mainly DHA in the intramuscular fat, but the increase was significantly higher when algae meal was administered with a bottle via RGR. This strategy could contribute to improvements in the marketing of lamb meat by optimizing its status as a healthier food.

Current intakes of trans-palmitoleic (trans-C16:1 n-7) and trans-vaccenic (trans-C18:1 n-7) acids in France are exclusively ensured by ruminant milk and ruminant meat: A market basket investigation

High circulating levels of trans-palmitoleic acid (TPA) are associated with a lower risk of type 2 diabetes in humans. Thus, the origin of circulating TPA matters. Direct intakes of TPA are ensured by dairy products, and perhaps by partially hydrogenated oils (PHOs). Indirect intakes of TPA rely on dietary trans-vaccenic acid (TVA), which occurs in ruminant-derived foods and PHOs. As it is usually assumed that PHOs are not used any longer, we analyzed here a wide range of foods currently available at retail in France. We report that TPA and TVA (1) do occur in ruminant milk and meat, dairy products and in foreign PHOs, (2) do occur in dairy fat-containing foods and (3) do not occur in dairy fat-free foods. Together, our findings demonstrate that ruminant fats are the only contributors to circulating levels of TPA in humans.

Identification and quantification of dimethyl acetals from plasmalogenic lipids in lamb intramuscular fat under different derivatization procedures

Meat lipids are mostly comprised by triacylglycerols, but small amounts of plasmalogens are also present in intramuscular fat. The purpose of this study was to evaluate the effect of lipid derivatization on the presence of dimethyl acetal (DMA) molecules from plasmalogenic lipids in intramuscular fat samples. Three different methods of methylation were assayed. Acid-catalyzed methanolysis using HCl, the traditional procedure to derivatize meat lipids, was compared to two base-catalyzed methanolysis based on the ISO International standard procedure using either KOH and/or NaOCH₃ which, apparently, are only able to methylate fatty acids from triacylglycerols. DMA compounds were isolated by thin layer chromatography and then identified by gas chromatography-mass spectrometry. The most prominent DMA molecules detected were 16:0 and 18:0, but also minor amounts of monounsaturated and branched-chain DMA were quantified. Acid methylation yielded the highest amounts of DMA. However, the present article demonstrates that ISO standard based methylation procedures could also generate DMA derivatives in considerable quantities, which is not usually considered and may interfere with the determination of fatty acid methyl esters (FAME) from triacylglycerides. The current research warns scientist about possible FAME misidentifying and overestimations in intramuscular fat analysis using basic methylation and the need to consider the presence of DMA in samples that contain plasmalogens.

Physicochemical and nutritional characteristics of Béni Guil lamb meat raised in eastern Morocco

BACKGROUND: The Béni Guil sheep is the main ovine breed that dominates livestock farming in the semi-arid region of eastern Morocco. No previous data is available on the quality of Béni Guil PGI (Protected Geographical Indication) lamb meat raised on the natural pasture of this area. OBJECTIVE: This study aims to provide the physicochemical and nutritional characteristics of Béni Guil PGI lamb meat. METHODS: Béni Guil PGI lamb meat was analysed for its quality parameters, fatty acid composition and amino acid profile. RESULTS: Results show that the Béni Guil PGI lamb meat has a significant juiciness (high water holding capacity), a marked tenderness (low collagen content) and a bright red colour. Longissimus lumborum muscle from Béni Guil PGI lambs contains 25.72% dry matter, including 19.43% protein, 5.14% fat, and 0.94% minerals. Gas chromatography-flame ionisation detection, for fatty acid analysis, revealed 49.45% saturated fatty acids (SFA), 38.48% monounsaturated fatty acids (MUFA) and 12.4% polyunsaturated fatty acids (PUFA). The UFA:SFA and n-6:n-3 PUFA ratios were 1.04 and 3.78, respectively, and were comparable to those recommended for a balanced diet. The amino acid analysis, allowed the identification of eight essential amino acids. The chemical index and the protein digestibility-corrected amino acid score values were 132 and 124, respectively. CONCLUSION: The results of this study indicate that the Beni Guil PGI meat has nutritional values in accordance with the nutritional recommendations and specific to the feeding system based mainly on grazing.

Changes in Lipid Oxidation and Fatty Acids in Altay Sheep Fat during a Long Time of Low Temperature Storage

Previously, we have shown that the fatty acid composition of Altay sheep tail fat is of reasonable value and is suitable for further development of possible commercial products. Changes in lipids of Altay sheep tail fat during 50 days of 4°C refrigerated storage were investigated. Lipid oxidation and lipolysis occurred during the storage. The pH showed a continually decreased from first day to the end of the storage (p < 0.05). The lipid oxidation was determined by peroxide value (PV) and thiobarbituric acid-reactive substances (TBARS). The increase PV was observed in Altay sheep fat up to 24 days of storage and decreased from then to the day 30 (p < 0.05). The increase in TBARS was significantly throughout the refrigerated storage (p < 0.05). The changes of the fatty acids identified by GS-MS demonstrated that saturated fatty acids increased from 43.6% to 56.3% and that polyunsaturated fatty acids and monounsaturated fatty acids decreased form 51.2% to 43.7% and from 2.4% to 2.1%, respectively. The content of the functional fatty acids except (C18:2 n-9), started to decrease after 20 days of storage. Those changes indicated that lipid oxidation occurred in Altay sheep tail fat during a long time of low temperature storage. In addition, the good correlation between PV/TBARS values and changes of individual fatty acids could be used as an indicator to monitor the changes of the unsaturated fatty acid during the development process of Altay sheep tail fat-related commercial products.

At slaughtering and post mortem characteristics on Traditional market ewes and Halal market ewes in Tuscany

BACKGROUND

The aim of this work was the comparison between the carcass and the meat ewes of the regional Traditional market and the Islamic religious (Halal) market.

METHODS

Thirty and 20 at the end of career traditional market and Halal market ewes were slaughtered following the EC (European Council, 2009) animal welfare guidelines. Live weight of ewes was taken and dressing percentage of carcasses was calculated. On every carcass zoometric measurement and the evaluation trough the EU grid rules were performed. On the Musculus longissimus thoracis of 12 Traditional market carcasses and 11 Halal market carcasses the physical-chemical and nutritional analysis were performed. Consumer tests for liking meat ewe were performed in order to find consumer's preference level for Traditional and Halal markets ewe meat. Considering as fixed factor the ewe meat market (Traditional and Halal), results were submitted to oneway Analysis of Variance (ANOVA) and to Principal Component Analysis (PCA).

RESULTS

The Halal market ewes have shown lower dressing percentages (42.91 ± 0.82 vs 46.42 ± 0.69) and lower conformation score (4.5 ± 0.5 vs 7.8 ± 0.4). The Halal market meat showed higher cooking loss in oven (37.83 ± 1.20 vs 32.03 ± 1.15 %), lesser Chroma value (18.63 ± 0.70 vs 21.84 ± 0.67), and lesser Hue angle value (0.26 ± 0.02 vs 0.34 ± 0.02). This product had also lower fat percentage (4.2 ± 0.4 vs 7.09 ± 0.4). The traditional market meat had higher percentage in monounsatured fatty acids (MUFA) (43.84 ± 1.05 vs 38.22 ± 1.10), while the Halal market meat had higher percentage in ω3 poliunsatured fatty acids (PUFA) (5.04 ± 0.42 vs 3.60 ± 0.40). The consumer test showed as the ewe meat was appreciate by the consumers.

CONCLUSIONS

Both meat typologies have shown good nutritional characteristics. The traditional market meat had higher MUFA composition, and a better MUFA/satured fatty acids (SFA) ratio, while the Halal market meat had higher PUFA composition. These results were also supported by the PCA. The consumers preferred the traditional market meat.

Characterization of the fatty acid composition of lamb commercially available in northern Spain: Emphasis on the trans-18:1 and CLA content and profile

A survey of commercially available lamb meat was performed in northern Spain in order to evaluate their fatty acid (FA) composition with emphasis on trans fatty acid (TFA) and conjugated linoleic acid (CLA) isomers. Samples were collected in spring (n=24) and winter (n=24) of 2013, and were obtained in about equal numbers from grocery stores and butcher-shops. Subcutaneous fat, known to be a sensitive indicator of TFA content in ruminants, was analyzed by GC-FID. In general, very few differences were observed between collection periods and type of stores because of the high variability within the groups that was believed to be associated with differences in genetics and feeding strategies. However, the 10t/11t ratio of all samples showed two clearly identifiable groups irrespective of the source: 1) when 10t/11t was >1, 10t-shifted samples; 2) when 10t/11t was ≤1, non-shifted samples where 11t-18:1 was the predominant isomer. These two groups were clearly identified and associated with distinct FAs using principal component analysis.

Detailed dimethylacetal and fatty acid composition of rumen content from lambs fed lucerne or concentrate supplemented with soybean oil

Lipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets supplemented with soybean oil. The methodological approach developed consisted on a basic/acid direct transesterification followed by thin-layer chromatography to isolate fatty acid methyl esters from dimethylacetal, oxo- fatty acid and fatty acid dimethylesters. The dimethylacetal composition was quite similar to the fatty acid composition, presenting even-, odd- and branched-chain structures. Total and individual odd- and branched-chain dimethylacetals were mostly affected by basal diet. The presence of 18:1 dimethylacetals indicates that biohydrogenation intermediates might be incorporated in structural microbial lipids. Moreover, medium-chain fatty acid dimethylesters were identified for the first time in the rumen content despite their concentration being relatively low. The fatty acids containing 18 carbon-chain lengths comprise the majority of the fatty acids present in the rumen content, most of them being biohydrogenation intermediates of 18:2n-6 and 18:3n-3. Additionally, three oxo- fatty acids were identified in rumen samples, and 16-O-18:0 might be produced during biohydrogenation of the 18:3n-3.

Ergosterol profiles, fatty acid composition, and antioxidant activities of button mushrooms as affected by tissue part and developmental stage

This article investigated the mycochemical profiles and the antioxidant activities of the lipophilic extracts of the white and brown button mushrooms. We found that only free ergosterols were present in both mushrooms at 2.04-4.82 mg/g dry matter (DM). Ergosterol concentration was higher in early growth stages but decreased as the mushrooms grew, and it distributed evenly between the caps and stems during early developmental stages but accumulated more in the caps after maturation. The photochemiluminescence (PCL) values of the two mushrooms were 5.49-10.48 nmol trolox equivalent/mg DM, and the EC50 values of 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay ranged 20.19-41.49 mg DM/μg DPPH. The ergosterol content positively correlated with the antioxidant activities (r2>0.89). The total fatty acid content was 8.7 mg/g DM in the white and 5.1 mg/g DM in the brown button mushroom and contained mainly linoleic, palmitic, and stearic acids. Our data provide guidance for optimized harvesting time of mushrooms and maximized health benefits.

A simulation model for the prediction of tissue:plasma partition coefficients for drug residues in natural casings

Tissue residues arise from the exposure of animals to undesirable substances in animal feed materials and drinking water and to the therapeutic or zootechnical use of veterinary medicinal products. In the framework of this study, an advanced toxicokinetic model was developed to predict the likelihood of residue disposition of licensed veterinary products in natural casings used as envelope for a variety of meat products, such as sausages. The model proved suitable for the calculation of drug concentrations in the muscles of pigs, cattle and sheep, the major species of which intestines are used. On the basis of drug concentrations in muscle tissue, the model allowed a prediction of intestinal concentrations and residues in the intestines that remained equal to or below the concentrations in muscle tissue, the major consumable product of slaughter animals. Subsequently, residues in intestines were found to be below the maximum residue limit value for muscle tissue when drugs were used according to prescribed procedures, including the application of appropriate withdrawal times. Considering the low consumption of natural casings (which represents only about 1-2% of the weight of a normal sausage), it was concluded that the exposure to drug residues from casings is negligible.

Significance of coprophagy for the fatty acid profile in body tissues of rabbits fed different diets

Four groups of eight New Zealand hybrid rabbits were fattened with ad libitum access to the following pelleted experimental diets: ryegrass meal or alfalfa meal fed either alone or with oats meal in a ratio of 1:1. After 25 weeks they were slaughtered and dissected. Fatty acid (FA) profiles of caecotrophs (re-ingested fermentation products of the caecum), perirenal adipose tissue and intramuscular fat in the Musculus quadriceps were determined. With high proportions of branched-chain FA (BFA) and trans FA, and increased proportions of saturated FA relative to the diets, the caecotroph FA profile showed a clear fingerprint of anaerobe microbial lipid metabolism including biohydrogenation. By contrast, the FA profiles of adipose and lean tissue comprised high proportions of polyunsaturated FA (PUFA), whilst BFA and trans FA occurred in much lower proportions compared to the caecotrophs. Thus, coprophagy did not substantially modify the FA composition of the tissues investigated. Use of forage-only diets, compared to the oats supplemented diets, led to extraordinary high proportions of n-3 PUFA (including 18:3 and long-chain n-3) in the fat of adipose (21.3 vs. 6.7%) and lean tissue (15.4 vs. 5.7%). The forage type diet (grass vs. alfalfa) had smaller effects on the FA profiles. Indications of diet effects on endogenous desaturation, chain elongation and differential distribution of functional FA between the two tissues investigated were found.

Extensive analysis of long-chain polyunsaturated fatty acids, CLA, trans-18:1 isomers, and plasmalogenic lipids in different retail beef types

The objective of this investigation was to provide a comprehensive analysis of the total lipid composition of present-day retail beef meat available at the consumer level and to evaluate the total lipid composition with special emphasis on the nutritional value. For this purpose, 40 beef cuts were obtained from four cattle farms based on either a natural grazing system (NGS) or an intensive production system (IPS). The total lipid composition was analyzed using complementary chemical and chromatographic procedures. The content of n-3 LC-PUFA, CLA, total trans-18:1, and branched-chain fatty acids was significantly higher in NGS beef than in IPS beef. The trans-18:1 and CLA profiles were affected by the different production systems, whereby they can be utilized empirically to differentiate between feeding regimen and production management. Fatty acid ratios that have health implications ( n-6/ n-3, LA/alphaLNA, and AA/EPA) were remarkably beneficial for NGS beef compared with IPS beef. In conclusion, from the human health perspective, beef raised on NGS is clearly superior with regard to a more favorable fatty acid profile in comparison to IPS beef.