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The study aimed to evaluate the effects of Allium mongolicum Regel (AMR) and its water‐ and fat‐soluble extracts on the quality of fermented mutton sausages. Sausages were produced with mutton and fat. Four treatments: CO, without Allium mongolicum Regel and its extracts, used as control; AMR with Allium mongolicum Regel; AWE with water‐soluble extract of Allium mongolicum Regel; and AFE with liposoluble extract from Allium mongolicum Regel, were produced and analyzed for pH, water activity (aw), free amino acids, fatty acids, and volatiles were, respectively, in fermented mutton sausages during processing (0, 2, 5, and 7 days). The results showed that the pH values of the liposoluble extract from Allium mongolicum Regel (AFE), respectively, are lower than that of sample CO at the end of fermentation and ripening. The aw in all group of sausages significantly dropped to 0.88 at the end of ripening (Day 7). Adding Allium mongolicum Regel and its water‐soluble extract can improve the serine (SER) content of fermented mutton sausage. The contents of five essential amino acids (EAA) were added when adding Allium mongolicum Regel and its fat‐soluble extract. The total fatty acid (TFA) in the treatments increased during drying and ripening. The addition of Allium mongolicum Regel and its extract can increase the content of volatile flavor substances such as 3‐hydroxy‐2‐butanone, 3‐methylbutyraldehyde, hexanal, octanal, and nonanal at the later stage of maturity, so as to improve the flavor substances in fermented mutton sausage. Water‐soluble extract of Allium mongolicum Regel (AWE) and AFE treatments had more intense flavor at the end of ripening (Day 7). The flavor of fermented mutton sausage can be improved by adding Allium mongolicum Regel and its extracts into fermented mutton sausage. [ABSTRACT FROM AUTHOR]

In this study, jerky samples were prepared from seasoned beef with and without the addition of starter culture. They were then dried or fried and analyzed to identify the quality parameters and volatile flavor compounds. Samples (starter and control) were divided into drying (inoculated‐drying, I‐D; noninoculated‐drying, N‐D) and frying (inoculated‐frying, I‐F; noninoculated‐frying, N‐F) groups. Water activity (aw), lightness (L*), and redness (a*) values were significantly affected (p <.001) by the postcooking procedures (drying or frying). Hardness, chewiness, and resilience were significantly lower in the dried groups than in the fried groups (p <.05). The formation of volatile compounds was affected by cooking treatment, with the highest levels observed in the I‐F group. After frying, the most abundant flavor compounds in the I‐D and N‐D groups were terpenes and sulfur‐containing compounds, followed by aromatic hydrocarbons, ketones, and alcohols. The most common compounds among all groups were acetoin, D‐limonene, anethole, styrene, and tetramethylpyrazine. Overall, the jerky in the I‐F group had the best color and tenderness scores among all groups. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of inoculation with different mixed starter culture combinations on microbial counts, physico‐chemical properties, and proteolytic and lipolytic properties of dry fermented mutton sausages during fermentation and ripening. Four different batches of mutton sausages were manufactured: CO batch, no starter cultures, used as control; LB batch with Lactobacillus sakei; LS batch with L. sakei + Staphylococcus xylosus; and LSS batch with L. sakei + S. xylosus + Staphylococcus carnosus. The results showed that adding starter culture caused Lactobacillus and Staphylococcus to become dominant bacteria and reduced the Enterobacteriaceae count in the inoculated sausages. The mixed starter cultures (LS & LSS) accelerated acidification and reduced water activity and lipid oxidation. Statistical analysis revealed that the use of mixed starter cultures, especially the combination L. sakei + S. xylosus + S. carnosus, contributed to proteolysis and lipolysis, increasing total free amino acids and polyunsaturated fatty acids. The above results demonstrate that the use of mixed starter cultures contributes to improving the composition of free amino acids and free fatty acids as well as the hygienic quality of dry fermented mutton sausages. [ABSTRACT FROM AUTHOR]

The biogenic amines (BAs), water activity, pH, thiobarbituric acid‐reactive substances (TBARS), and nitrite were, respectively, tested in dry fermented sausage with starter cultures (37x‐6 Lactobacillus plantarum, x3‐3b L. plantarum, 30x‐11 Staphylococcuspentosans, and 37x‐8 S. pentosans), during storage of room temperature (20°C) and refrigeration storage (4°C). Tryptamine (TRM), 2‐phenylethylamine (PHE), putrescine (PUT), cadaverine (CAD), histamine (HIM), and tyramine (TYM) contents of all samples were increased storage at 20°C, and the content of TRM, PUT, CAD, and HIM of all samples storage at 20°C was higher than that storage at 4°C after 42 days. The content of BA with 37x‐6, x3‐3b, and 37x‐8 was obviously decreased at 4°C storage. The storage temperature has a significant effect on BA content (p <.05) for TYM and other BAs tested. Finally, x3‐3b, 37x‐6, and 37x‐8 should be used to produce fermented sausages on the basis of the concentration of BAs. [ABSTRACT FROM AUTHOR]

This study investigated the effects of probiotics on growth performance, meat quality, muscle fiber characteristics, volatile compounds, and antioxidant capacity in lambs. A total of 24 Sunit lambs were randomly allocated into two groups, each consisting of three replicates of four lambs. Throughout the experiment period, the lambs were fed with based diet (CON) and 10 g probiotics/d supplemented diet (PRO). Compared with the CON group, the number of lactic acid bacteria in fecal samples of PRO group was significantly increased (p <.05) and the coliforms were significantly decreased (p <.05). Dietary probiotics supplementation decreased pH24h, L*, and shear force (p <.05). The muscle fibers were switched from type IIB to type I, with a decrease in the mean cross‐sectional area (CSA) (p <.05) of longissimus thoracis (LT) muscle. Also, probiotics altered the composition of meat volatile flavor compounds, such as nonanal, undecanal, 1‐pentanol, 1‐hexanol, and 2,3‐octanedione. In addition, probiotics increased the total antioxidative capacity (T‐AOC) and catalase (CAT) activity of LT muscle, while it decreased superoxide dismutase (SOD) activity (p <.05). Overall, these results indicated that probiotics could be used as an effective feed additive by improving meat tenderness and flavor. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of exercise training on muscle metabolism, fatty acid composition, carcass traits, and meat quality characteristics of Mongolian sheep. Fourteen Mongolian sheep were randomly divided into two groups (7 sheep in each) and placed in two adjacent livestock pens. One group of sheep was kept in the pen (Control [C] group) and the other group of sheep (Training [T] group) were driven away in a field to walk twice a day. The results showed a reduction in pH measured 45 min post mortem, L*, a*, and b* value, intramuscular fat, and carcass length, and an increase in the ultimate pH value and shear force in the meat of T group in comparison with that of C group (p <.050). Also, exercise training moderately affected the fatty acid composition of LT muscle. Compared with C group, the concentrations of myristoleic acid (C14:1) and stearic acid (C18:0) were increased (p <.050), while the concentrations of C20:3 n‐6, neurolic acid (C24:1), and n‐3 polyunsaturated fatty acid (PUFA) were decreased in T group (p <.050). Transcriptome analysis highlighted 621 genes differentially expressed in two groups, including 385 were up‐regulated (e.g., GLUT4 and PGC‐1α) and 236 were down‐regulated (e.g., PLIN1 and ACSL3) in T with respect to C group. Besides, considering these genes, a number of enrichment pathways related to muscle metabolic processes, involving carbohydrate metabolism, lipid metabolism, oxidation reduction process, and muscle tissue development, were highlighted. In conclusion, these results contributed to a better understanding of the possible biological and molecular processes underlying the effects of exercise training on muscle metabolism and meat quality in Mongolian sheep, and provide useful information for contributing to understand the phenotypic and functional differences in meat quality of sheep. [ABSTRACT FROM AUTHOR]

To investigate the effects of the activator of AMPK and high glucose on the differentiation of mouse SMSCs, primary SMSCs were isolated from mouse extensor digitorum longus muscle and grown to near confluence (80%). Postconfluent cells were cultured in a growth medium with different inductors: AICAR, glucose, and AICAR mixed with glucose. The specific protein expressions of SMSCs, myoblasts, adipocytes, and brown adipocytes were analyzed on days 0, 3, 5, 7, and 10. The results showed treatment with AICAR in SMSCs markedly activated AMPK phosphorylation (p <.05) and increased protein expression of Pax7 and MyoD (p <.05), high concentrations of intracellular glucose upregulated UCP‐1 protein expression and enhanced lipid accumulation (p <.05), the cowork of AICAR and glucose affected a decrease on MyoD, PPARg, and UCP‐1 expression (p <.05) and an increase on Pax7. The present study indicated that the certain energy supplements influence the direction of SMSC differentiation which may contribution on the structure of muscle and meat quality, sequentially. [ABSTRACT FROM AUTHOR]

Astragalus membranaceus (AM) provides a rich source of polysaccharides that can act as powerful antioxidants, but their potential as feed ingredients in the lamb industry still rarely exploited. The objective of this study was to investigate the effect of dietary astragalus membranaceus supplementation on oxidative stability of goat muscles. Longissimus dorsi (LD) muscles from two groups of Cashmere goat (basal diet, C group; basal diet supplemented with 1% astragalus membranaceus root, AM group) were evaluated for lipid oxidation, myoglobin oxidation, activity of antioxidant enzymes, and antioxidant capacity. The results showed that color parameters in Cashmere goat of two feeding conditions were no significant difference (p >.05). In AM group, myoglobin (Mb) content was higher than C, while metmyoglobin (MMb) (p <.05) and malondialdehyde (MDA) (p <.01) were lower. Additionally astragalus membranaceus supplementation had a significant effect on superoxide dismutase (SOD) and catalase (CAT) (p <.001). In whole, the AM group goats presented a relatively higher antioxidant capacity than C. Especially, RSA and CUPRAC values of AM group goats had significantly higher than C (p <.05). Consequently, the AM group goats ingested abundant astragalus membranaceus, which enhanced the antioxidant capacity. Thus, it can eliminate free radicals and effectively inhibit oxidation. [ABSTRACT FROM AUTHOR]

The effects of two feeding regimens on meat quality, myosin heavy chain (MyHC) types, and key factors regulating muscle fiber type (AMP‐activated protein kinase [AMPK] and peroxisome proliferator‐activated receptor‐coactivator‐1α [PGC‐1α]) in the biceps femoris muscle of Mongolia sheep were investigated. A total of 20 Mongolia sheep were weaning for 90 days and divided into two groups (pasture group (P) and confinement group (C)) at 10.36 ± 0.35 kg of weaning weight. After weaning, sheep were pasture fed or confinement fed for 9 months. The results showed that live weights, carcass weight, intramuscular fat (IMF), and Warner–Bratzler shear force (WBSF) in P group were significantly lower (p <.05) than that in C group. Compared with P group, color evaluations with respect to L* and b* values were significantly higher (p <.05) in C group. Expression of the MyHC I gene in the P group was significantly higher, while MyHC IIa and MyHC IIb genes expression was significantly lower (p <.05) than that in C group. Also, AMPK activity and expression of AMPKα2 and PGC‐1α genes were significantly higher (p <.05) in P group compared with C group. The present study indicated that muscle fiber composition was one of the key differences leading to the differences of meat quality in different feeding regimens. AMPK, particularly AMPKα2, and PGC‐1α were considered to be two key factors regulating muscle fiber types in Mongolia sheep. The results support that AMPK activity and the expression of AMPKα2 and PGC‐1α genes may affect the composition of muscle fibers; thus, AMPK activity and the expression of AMPKα2 and PGC‐1α genes had an effect on meat quality by changed composition of muscle fibers. [ABSTRACT FROM AUTHOR]

The aim of the present work was to investigate the effects of feeding regimens (pasture vs. mixed diet) on meat quality, fatty acids, volatile compounds, and antioxidant properties in lamb meat. In total, 24 lambs were allotted into two feeding regimens at 10.23 kg live weight. Lambs were fed on pasture grass (PG group, n = 12) or mixed diet (M group, n = 12). Longissimusthoracis (LT) muscle samples from the M group had a higher intramuscular fat (IMF) (p < 0.05), pH45minvalue (p < 0.01), and ash (p < 0.05) than the PG group. In contrast, the shear force (p < 0.05), L*(p < 0.05), and b* (p < 0.001) in M group were lower than in PG group. Analyses indicated that PG group contained higher linolenic acid (C18:3n3) and docosatrienoic acid (C22:3n6) (p < 0.05) than the M group. Major volatile compounds in the muscles included hexanal, heptanal, nonanal, octanal, 1‐pentanol, 1‐hexanol, 1‐octen‐3‐ol, and 2,3‐octanedione. The levels of hexanal, nonanal, and 2,3‐octanedione were significantly lower in PG lamb muscle (p < 0.01). In contrast, 1‐pentanol and 1‐hexanol levels were higher in M lamb muscle (p < 0.01). Muscle from PG lamb exhibited higher catalase (CAT) and glutathione peroxidase (GPx) activity (p < 0.05). PG muscle also contained a higher radical‐scavenging ability (RSA; p < 0.001) and cupric‐reducing antioxidant capacity (CUPRAC; p < 0.05). Overall, the improved antioxidant status in PG muscle inhibited lipid peroxidation (aldehydes and ketones), thereby improving the meat quality. [ABSTRACT FROM AUTHOR]