Yanbian cattle have a unique meat flavor, and high-grade meat is in short supply. Therefore, in this study, we aimed to improve the added value of Yanbian cattle low-fat meat and provide a theoretical reference for the subsequent development of an excellent starter. Rump meat from Yanbian cattle was dry-aged and then screened for protease-producing fungi. Three protease-producing fungi (Yarrowia hollandica (D4 and D11), Penicillium oxalicum (D5), and Meesziomyces ophidis (D20)) were isolated from 40 d dry-aged beef samples, and their ability to hydrolyze proteins was determined using bovine sarcoplasmic protein extract. SDS-PAGE showed that the ability of Penicillium oxalicum (D5) to degrade proteins was stronger than the other two fungi. In addition, the volatile component content of sarcoplasmic proteins in the D5 group was the highest (45.47%) and comprised the most species (26 types). Metabolic pathway analysis of the fermentation broth showed that phenylalanine, tyrosine, and tryptophan biosynthesis was the most closely related metabolic pathway in sarcoplasmic protein fermentation by Penicillium oxalicum (D5). Dry-aged beef-isolated Penicillium oxalicum serves as a potential starter culture for the fermentation of meat products.
Dry-aging is a postmortem process that can substantially enhance the texture and flavour of beef. This study entailed suspending Yanbian cattle M. gluteus medius in the aging cabinet, maintained at a temperature of 2–4 °C and a relative humidity of 85 ± 5% for 35 days. Throughout this period, samples were systematically collected every 7 days. The widely targeted metabolomic analysis has been used in this investigation to analyse the dynamic changes in Yanbian cattle metabolites during dry-aging. A total of 883 metabolites were identified, with amino acids and their metabolites representing the largest proportion. Multivariate statistical analysis showed that 373 metabolites were identified as differential metabolites that changed significantly during the dry-aging process, including metabolites of amino acids, glycerophospholipids, and nucleotides and their metabolites. Additionally, 308 metabolites exhibited various increasing trends with time in dry-aging. The analysis of KEGG pathway analysis showed that ABC transporters, glycerophospholipid, and arachidonic acid metabolism are the most important metabolic pathways during dry-aging. These findings can guide technological developments in the meat processing sector and provide valuable insights into the metabolic traits and pathways of Yanbian cattle during the dry-aging process.
This study aimed to elucidate the effects of different fattening stages on slaughtering performance, meat quality, muscle fiber characteristics, connective tissue properties, and intramuscular fat deposition in Yanbian cattle. A total of 40 eighteen-month-old castrated male Yanbian cattle were raised together under identical conditions. At 24, 28, 32, and 36 months of age, 10 animals were randomly selected and slaughtered. Increased fattening periods, slaughter performance of Yanbian cattle improved steadily, carcass weight and meat weight increased significantly (p < 0.05). Dressing percentage and lean meat percentage reached their maxima at 32 months, which were 60.09% and 46.96% respectively. Cooking loss and centrifugal loss decreased with fattening time (p < 0.05), with the 32- and 36-month-old groups showing the best water-holding capacity. Intramuscular fat content increased significantly during fattening (p < 0.05), with no significant difference between the 32- and 36-month-old groups (p > 0.05). However, Warner–Bratzler shear force (WBSF) was significantly higher at 32 and 36 months than at 24 and 28 months (p < 0.05), indicating reduced tenderness with prolonged fattening. The endomysial collagen network at 32 months maintained a compact yet filamentous structure, whereas by 36 months it had transformed into a dense sheet-like configuration. In conclusion, fattening to 32 months achieves a compromise among marbling, collagen maturity, water-holding capacity, slaughtering efficiency, and the onset of increased toughness. Therefore, 32 months is recommended as the fattening endpoint when balancing meat production and quality traits.