Interactive effects of wet-aging and slaughter age on physicochemical and taste-related characteristics of Hanwoo beef loin

The effects of slaughter age and aging on Hanwoo beef quality have been previously demonstrated, but comprehensive understanding of their interaction is lacking. This study evaluated how aging period (1, 14, and 28 days) and slaughter age (24-, 26-, 28-, and 30-months) affected physicochemical meat quality and taste-related compounds in Hanwoo beef loin. Aging significantly improved beef eating quality through decreased shear force, increased myofibrillar fragmentation index, elevated umami- and sweet-tasting free amino acids, and enhanced sensory preference. However, aging caused high purge loss and degradation of taste nucleotides. The equivalent umami concentration remained unchanged during aging, whereas five taste compounds (inosine monophosphate, Glu, His, Ala, and Tyr) exhibited taste activity values above one, highlighting their importance in aged beef taste. Slaughter age affected meat quality traits and taste compounds, including fatty acid composition. Interactions between aging and slaughter age were observed for purge loss, myofibril fragmentation index, yellowness, and several nucleotides and free amino acids, showing these traits were regulated by both factors. Partial least squares discriminant analysis identified aging period as the primary factor shaping taste profiles, with 19 compounds (three nucleotides and six free amino acids) showing variable importance in projection scores >1.0, of which 17 correlated strongly with three meat quality parameters (purge loss, shear force and myofibrillar fragmentation index). This study demonstrated that postmortem aging enhanced Hanwoo beef eating quality by improving tenderness and taste-related compounds, even in short-term reared cattle, and provided insights for optimizing aging strategies for sustainable, and value-added production.