Fatty Acid Composition and Volatile Profile of M. longissimus thoracis from Commercial Lambs Reared in Different Forage Systems

Effect of hay type and breed on the fattening, centesimal and fatty acid composition of Nigerian sheep

This study aimed to evaluate the intake, performance, quality, and fatty acids (FA) composition of the meat of three Nigerian sheep breeds (Balami, Uda, and Yankasa) fed two different hays, Brachiaria decumbens or Digitaria smutsii. A total of sixty sheep, twenty from each breed, Balami, Uda, and Yankasa, were used, with average body weights of 24.7 ± 3.5 kg, 25.5 ± 3.6 kg, and 25.5 ± 3.5 kg, respectively. The sheep were arranged in a factorial 2 (hay types) × 3 (breeds) design within a completely randomized setup, totalling ten experimental units per treatment. There was no significant (p > 0.05) interaction effect between breed and hay type on any variables. Sheep-fed D. smutsii hay presented higher (p ≤ 0.05) DM intake from the concentrate, hay, total feed, final BW, ADG, intramuscular fat, and FA contents than sheep-fed B. decumbens, except for 18:1n-9, where sheep fed B. decumbens presented higher (p ≤ 0.05) concentration. Balami sheep presented higher (p ≤ 0.05) total weight gain than the Uda breed and once performed better than the Yankasa breed, without difference (p > 0.05) to feed efficiency. Longissimus lumborum of the Yankasa breed presented lower concentrations (p ≤ 0.05) of total polyunsaturated FA (PUFA) than Balami and Uda sheep. The content of n-3 and n-6 PUFA (linolenic, EPA, DPA, and DHA), n-6/n-3 ratio, and EPA + DHA were higher in the Balami sheep than in the Uda sheep. Balami breed had the highest carcass weight and meat protein content but had a lower (p ≤ 0.05) moisture content than other breeds. Uda and Yankasa sheep presented similar moisture content (p ≤ 0.05). However, the carcass weight, protein, and fat content of the longissimus lumborum were higher (p ≤ 0.05) in Uda compared to Yankasa sheep. Nigerian sheep fed D. smutsii hay compared to B. decumbens hay to provide greater DM intake, improving fattening and meat fat and increasing all fatty acids in the longissimus lumborum. Balami breed presented greater DM intake, performance, and carcass weight, and consequently higher intramuscular fat deposition and concentration of most fatty acids in the longissimus lumborum than the breeds Uda and Yankasa.

Internal endpoint temperature (level of cooking doneness) effects on the fatty acid and mineral profiles of grilled lamb m. longissimus lumborum

This study compared the fatty acid and mineral concentrations of lamb meat that was prepared to different levels of cooking doneness. Ten m. longissimus lumborum were each sectioned into 4 slices that were randomly assigned to be uncooked or grilled to an internal end-point temperature of 60 °C (rare), 71 °C (medium), or 77 °C (well done). It was found that cooking loss increased as the level of cooking doneness increased. The proportion of most major fatty acids were not altered by cooking. However, when adjusted for cooking loss (i.e., mg/135 g serve of lamb as-is equivalent prepared to each level of cooking doneness), the concentration of most major fatty acids, including C16:0, C18:0, C18:1n-9, and many conjugated linoleic acids, were lowered after grilling to any level of cooking doneness and compared to the uncooked samples. The omega-6 to omega-3 ratio was lowest for the uncooked samples and highest for those prepared to a well done level of cooking doneness. Conversely, the concentration of health claimable omega-3 fatty acids in the uncooked meat was retained upon cooking and across all the different internal endpoint temperatures. Calcium, magnesium, phosphorous, potassium, and sodium were reduced with preparation of lamb meat to any level of cooking doneness, compared with uncooked meat. Zinc, iron, and selenium were retained within the cooked samples. These findings show that consumer preference for a level of cooking doneness will have only minor effects on the concentration of minerals and fatty acids in lamb meat.

Molecular insights into quality and authentication of sheep meat from proteomics and metabolomics

Sheep meat (encompassing lamb, hogget and mutton) is an important source of animal protein in many countries, with a unique flavour and sensory profile compared to other red meats. Flavour, colour and texture are the key quality attributes contributing to consumer liking of sheep meat. Over the last decades, various factors from 'farm to fork', including production system (e.g., age, breed, feeding regimes, sex, pre-slaughter stress, and carcass suspension), post-mortem manipulation and processing (e.g., electrical stimulation, ageing, packaging types, and chilled and frozen storage) have been identified as influencing different aspects of sheep meat quality. However conventional meat-quality assessment tools are not able to elucidate the underlying mechanisms and pathways for quality variations. Advances in broad-based analytical techniques have offered opportunities to obtain deeper insights into the molecular changes of sheep meat which may become biomarkers for specific variations in quality traits and meat authenticity. This review provides an overview on how omics techniques, especially proteomics (including peptidomics) and metabolomics (including lipidomics and volatilomics) are applied to elucidate the variations in sheep meat quality, mainly in loin muscles, focusing on colour, texture and flavour, and as tools for authentication. SIGNIFICANCE: From this review, we observed that attempts have been made to utilise proteomics and metabolomics techniques on sheep meat products for elucidating pathways of quality variations due to various factors. For instance, the improvement of colour stability and tenderness could be associated with the changes to glycolysis, energy metabolism and endogenous antioxidant capacity. Several studies identify proteolysis as being important, but potentially conflicting for quality as the enhanced proteolysis improves tenderness and flavour, while reducing colour stability. The use of multiple analytical methods e.g., lipidomics, metabolomics, and volatilomics, detects a wider range of flavour precursors (including both water and lipid soluble compounds) that underlie the possible pathways for sheep meat flavour evolution. The technological advancement in omics (e.g., direct analysis-mass spectrometry) could make analysis of the proteins, lipids and metabolites in sheep meat routine, as well as enhance the confidence in quality determination and molecular-based assurance of meat authenticity.

Effects of Dairy Lambs' Rearing System and Slaughter Age on Consumer Liking of Lamb Meat and Its Association with Lipid Content and Composition

The effects of the rearing system (artificially vs. naturally milk-fed) and the slaughter age (3-weeks milk-fed vs. 3-months pasture-fed) on consumer liking of East-Friesian-cross dairy lamb Longissimus lumborum muscle and its association with lipid content and composition were evaluated. The artificially reared lambs were removed from their dams at 2−3 days of age and reared with cow milk. Intramuscular fat content (2.8%) was similar between treatments. Only 3 of the 25 fatty acids evaluated were influenced by the rearing system and 15 by the slaughter age. The rearing system had a minor impact (p < 0.10), but the slaughter age had a major (p < 0.01) impact on consumer liking. All consumers preferred on average meat from 3-weeks-old lambs. However, based on overall liking scores, Cluster-1 (60% of consumers) preferred meat from 3-weeks-old lambs driven by all sensory attributes but mostly tenderness, whereas Cluster-2 preferred meat from 3-months-old lambs driven by flavor only, indicating a preference for stronger flavor from older lambs finished on pasture. Meat fatty acid profile and consumer liking were not influenced by the rearing system but by lamb slaughter age, showing a niche product opportunity for the 3-weeks milk-fed lambs.

Comparative Analyses of Production Performance, Meat Quality, and Gut Microbial Composition between Two Chinese Goose Breeds

Simple Summary

Poultry is one of the most frequently consumed meats in the world and plays an important role in the daily life of people. Goose meat is consumed by consumers because it contains a relatively high proportion of polyunsaturated fatty acids. Meat quality traits, production performance, and cecal microbiota diversity in two goose breeds (Zi goose and Xianghai flying goose) were evaluated in this study. Understanding these aspects not only provides a reference for the exploration of the relationship between the cecal microbiota and production performance but also guidelines for the human consumption of healthy poultry meat.

Abstract

Goose meat is consumed by consumers because it contains a relatively high proportion of polyunsaturated fatty acids (PUFAs). This study was conducted to explore the main differences in production performance, breast meat quality traits, and cecal microbiota compositions between the Zi goose (ZG) and Xianghai flying goose (FG). The production performance and breast meat quality trait analyses showed that compared with the ZG, the FG had a higher right breast muscle index, ileum villi height/crypt depth ratio (VH/CD), and cecum fermentation rate (higher short-chain fatty acid (SFCA) concentration); a lower abdominal fat index; a higher proportion of PUFAs; and a lower shear force. Spearman’s correlation coefficients between the cecal microbiota composition and production performance indexes suggested that the genus Faecalibacterium was positively associated with production performance; in contrast, the genus Candidatus Saccharimonas was negatively correlated with production performance; moreover, the Ruminococcus torques group, Parasutterella, and Methanobrevibacter were negatively related to the VH/CD. Taken together, in this particular trial, FG had better production performance, healthier meat quality traits, and better intestinal digestion and absorption capacities than ZG. These results not only provide a useful data reference for the production of healthy geese for human consumption but can also help guide the utilization of goose breed resources.

Assessment of components related to flavor and taste in Tan-lamb meat under different silage-feeding regimens using integrative metabolomics

Two untargeted metabolomics approaches based on gas chromatography mass spectrometry and ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry were used to identify the effects of different feeding regimes (concentrate, corn silage, alfalfa silage, mulberry leaf silage) on the potential meat flavor and taste components of Tan-lamb. Among 31 identified volatiles, hexanal was affected by the alfalfa silage diet, and 3-hydroxydodecanoic acid was changed by the mulberry leaf silage diet. l-Pipecolic acid (area under the curve = 1, fold change = 0.18-0.48) and trimethylamine N-oxide (area under the curve = 1, fold change = 5.26-22.84) was the potential best discriminant biomarker under alfalfa silage and concentrate feeding, respectively. The hydrophilic components were more readily changed by feeding regimes than volatile flavor compounds. Our findings are helpful for the illustration of Tan-lamb meat chemistry and producing high-quality lamb meat with improved flavor and taste by corn silage, alfalfa silage, or mulberry leaf silage.

Effects of oxidative stability variation on lamb meat quality and flavor during postmortem aging

This study evaluated the effects of oxidative stability variation on meat quality and flavor in biceps femoris (BF) and longissimus dorsi (LD) muscles of lambs during postmortem aging. The samples were stored at 4±1℃; the meat quality, flavor and muscle oxidative stability were measured on day 0, 1, 2, 3, and 4 of postmortem aging. The results showed that malondialdehyde (MDA) content increased in both muscle types; superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities decreased, as did total antioxidative capacity (T-AOC). LD muscle showed lower MDA content and antioxidative activity than BF muscle. Meat quality analyses indicated that aging increased the lightness (L*), redness (a*), and yellowness (b*) values of meat while improving its tenderness. Gas chromatography-mass spectrometry results showed that volatile flavor compounds were more abundant in LD muscle than in BF muscle. As the aging time extended, relative contents of aldehyde and alcohol increased in both muscles. The key flavor compounds during postmortem aging including heptanal, octanal, nonanal, and decanal were screened by relative odor activity value (ROAV), and the content of key flavor compounds showed the trend of increasing, which were usually associated with fresh green grass, nutty, and fat descriptors. In conclusion, the oxidative muscles displayed better antioxidative capacity, and postmortem aging altered the oxidative stability of lamb muscle, which affected the meat quality and flavor. PRACTICAL APPLICATION: Meat aging is an important strategy to improve the quality of various meat traits (including flavor). The results of this work could be of interest to meat professionals who will be able to apply in actual production by choosing the best aging time based on flavor and meat quality for different muscle parts.

Metabolic fingerprinting using Rapid evaporative ionisation mass spectrometry can discriminate meat quality and composition of lambs from different sexes, breeds and forage systems

Assurance of food quality and allied farming systems is increasingly sought by consumers and food processors. Yet, there are no validated analytical approaches for food-based verification of farming systems. Rapid evaporative ionisation mass spectrometry (REIMS) is an emerging analytical tool that can provide sufficient details to meet this need. M. Longissimus lumborum of 10 groups of lambs (n = 140) from 3 farms, varying by breed, sex, and forage type, were measured using REIMS fingerprinting. Modelling of features detected by REIMS could discriminate for most comparisons of sex (including castration status), breed, and diet. Tentative identification suggested that lipids, hormone-related compounds, amino acids and dipeptides were the main discriminatory features. Several REIMS features were correlated with pH and shear force in Merino lambs. REIMS was able to detect features related to breed, sex and feed in lamb meat, suggesting that these characteristics can be independently measured using rapid metabolic fingerprinting.

Semi-Quantitative and Qualitative Distinction of Aromatic and Flavour Compounds in Charcoal Grilled, Electric Barbecue Grilled, Infrared Grilled and Superheated-Steam Roasted Lamb Meat Patties Using GC/MC, E-nose and E-tongue

This study investigated the influence of four different methods of cooking (charcoal grilling, electric barbecue grilling, superheated-steam roasting and infrared grilling) on the volatile profile of lamb meat patties. The study included the patties of the oyster cut muscle of lambs cooked using charcoal grilling, electric barbecue grilling, infrared grilling and superheated-steam roasting methods. The principal component analysis (PCA) of electric nose data showed a total variance of 73.71%. The e-nose values showed differentiation of the volatiles released from the lamb meat patties. Data of PCA of e-nose and GC-MS revealed good separation between groups. Significance (p < 0.05) was found for the flavour profile values of charcoal-grilled and superheated-steam-roasted samples while the lowest significance was observed between infrared- and electric-barbecue-grilled samples. Saltiness and sourness were higher in superheated-steam-roasted patties than charcoal-grilled samples through e-tongue. The main volatile compound found in all the lamb patties was 2,3-octanedione with a content of 20.43 µg/g–27.83 µg/g. 1-hexanol was highest at 34.74 µg/g in the charcoal-grilled samples while 2,3-octanedione was highest at 35.83 µg/g in superheated-steam-roasted patties.

The effect of perennial and annual wheat forages, fed with or without lucerne, on the fatty acid profile and oxidative status of lamb meat

The current study investigated the fatty acid profile and oxidative status of the meat from lambs that were fed a novel perennial wheat or a conventional annual wheat, either as a cereal monoculture or lucerne biculture. Twelve lambs were assigned to each of the four dietary treatments (48 lambs in total) and held within individual pens for the duration of the 28 day feeding study. Lambs were slaughtered and the longissimus lumborum (LL) and semimembranosus (SM) muscles analysed. The independent effect of wheat type on fatty acid concentrations was negligible. The concentration of long-chain saturated and omega-6 polyunsaturated fatty acids was higher when lucerne was included in the diet. Only monounsaturated fatty acids were affected by the interaction between wheat type and lucerne. The three-way interaction between wheat type, lucerne and muscle was only significant for the concentration of C12:0 and anteiso-C15:0. The concentration of thiobarbituric reactive substances and vitamin E was higher in meat from lambs fed a lucerne biculture, compared with those fed a cereal monoculture. Furthermore, and independent to dietary treatment, higher concentration of omega-3, omega-6 and other health claimable fatty acids were found in the SM, compared with the LL. This information will support industry adoption of novel perennial wheat polycultures and help producers to utilise it as a dual-purpose crop for the production of grain and/or sheep meat.

Edible Far Eastern Ferns as a Dietary Source of Long-Chain Polyunsaturated Fatty Acids

Young fronds of ferns are consumed as a vegetable in many countries. The aim of this study was to analyze three fern species that are available for sale in the Russian Far East as dietary sources in terms of fatty acids that are important for human physiology: arachidonic acid (20:4n-6, ARA), eicosapentaenoic acid (20:5n-3, EPA) and other valuable long-chain polyunsaturated fatty acids. The content of ARA and EPA was 5.5 and 0.5 mg/g dry weight, respectively, in Pteridium aquilinum, 4.1 and 1.1 in Matteuccia struthiopteris, and 2.2 and 0.8 in Osmundastrum asiaticum. Salted fronds of P. aquilinum contained less these fatty acids than the raw fronds, with a decrease of up to 49% for ARA and 65% for EPA. These losses were less pronounced or even insignificant in dried fronds. Cooked ferns preserved significant portions of the long-chain polyunsaturated fatty acids: cooked P. aquilinum contained 4.4 mg/g dry weight ARA and 0.3 mg/g dry weight EPA. The ferns may provide a supplemental dietary source of these valuable long-chain polyunsaturated fatty acids, especially for vegetarian diets.

Reis M, Silcock P, Johnson PL, Realini CE. Relationships among Consumer Liking, Lipid and Volatile Compounds from New Zealand Commercial Lamb Loins

Loin sections (m. Longissimus lumborum) were collected at slaughter from forty-eight lamb carcasses to evaluate consumer-liking scores of six types of typical New Zealand commercial lamb and to understand the possible underlying reasons for those ratings. A consumer panel (n = 160) evaluated tenderness, juiciness, flavor liking, and overall liking of the different types of lamb loins. Consumer scores differed among the types of lamb meat for all the evaluated attributes (p < 0.05). Further segmentation based on overall liking scores showed two consumer clusters with distinct ratings. Correlation and external preference map analyses indicated that one consumer cluster (n = 75) liked lamb types that had lower total lipid content, a lower proportion of branched-chain fatty acids, oleic and heptadecanoic acids; and a higher proportion of polyunsaturated fatty acids and volatile compounds (green and fruity descriptors). Consumer liking of the other segment (n = 85) was less influenced by fatty acids and volatiles, except hexanoic, heptanoic and octanoic acids (rancid, fatty, and sweaty descriptors). Thus, the fatty acid profile and the volatile compounds derived from their oxidation upon cooking seem to be a stronger driver of consumer liking of lamb for some consumers than others.