Wet Aging for 21 Days Improves Tenderness of Beef Biceps Femoris Muscle Without Affecting Color Stability

Beef whole-muscle cuts containing biceps femoris (BF) exhibit inferior tenderness compared to cuts from the ribs and loins. The BF is a sizeable muscle in beef round, and enhancing tenderness of BF may increase the value of beef carcasses. While wet aging for 21 d improves beef tenderness, it can compromise color. Therefore, we evaluated the effects of wet aging on color and tenderness of beef BF to identify an optimal aging duration for these quality traits. The BF muscles were collected 24 h postmortem from 8 beef carcasses (n = 8), divided into equal sections, vacuum packaged, and aged at 2°C for 0, 7, 14, and 21 d. After aging, muscle sections were fabricated into steaks, overwrapped, and stored for 0, 3, or 6 d under refrigerated storage. Myoglobin concentration, shear force, pH, instrumental color, metmyoglobin reducing activity (MRA), and lipid oxidation were evaluated. Beef BF steaks aged for 21 d exhibited lower (P < .05) shear force than those aged for 0, 7, and 14 d indicating an increased tenderness. Additionally, the 7- and 14-d aged steaks demonstrated lower (P < .05) shear force than their nonaged counterparts. The BF muscles aged for 14 and 21 d exhibited lower (P < .05) myoglobin concentration compared to those aged for 0 and 7 d. Aged BF steaks (7, 14, and 21 d) demonstrated greater (P < .05) redness on days 0 and 3 of storage than the nonaged ones. Overall, MRA and color stability were not affected (P > .05) by aging, whereas lipid oxidation increased (P < .05) with aging and storage days. The results indicated that 21 d of wet aging could be a practical strategy to improve the tenderness of BF steaks without compromising the surface color.