Yarrowia parophoni from Chongkukjang enhances sarcoplasmic protein hydrolysis and volatile flavor formation in beef during low-temperature fermentation

During the dry-aged beef, yeasts with high protease activity can hydrolyze proteins, thereby increasing the concentration of free amino acids. In this study, we screened the yeast based on its protease activity, safety experiments, and adaptability to low temperatures. This process yielded four strains with high protease production and strong low-temperature adaptability. Among them, strain Q3-6 demonstrated outstanding performance in the beef muscle protein fermentation model. This strain significantly increased the content of TCA soluble peptides and free amino acids, resulting in a threefold increase in the TCA soluble peptide content while also increasing by 31.53 ± 0.25 mg/L. At the same time, it also enriched volatile flavor compounds, including aldehydes, alcohols, and ketones. Based on ITS DNA sequencing, Q3-6 was identified as Yarrowia parophoni . This yeast strain demonstrated a targeted hydrolysis of sarcoplasmic proteins and an enhancement of meat flavor characteristics. Our findings indicate that Yarrowia parophoni , isolated from Chongkukjang, has potential as a starter culture for the low-temperature fermentation of dry-aged meat products. This work provides a theoretical foundation for developing strategies to enhance meat flavor.