Predictors of Beef Tenderness: Development and Verification

Equations were developed to predict beef longissimus dorsi (LD) tenderness after postmortem refrigerated aging. Warner‐Bratzler shear force (WBSF) and myofibril fragmentation indices (MFI) were determined at 1, 3, 7 and 14 days postmortem on LD of Angus‐Hereford (AH, n = 8) and 5/8 Brahman crossbred (n = 8) heifer carcasses. Correlation coefficients between WBSF and MFI were −0.91, −0.74, −0.63, and −0.40 at 1, 3, 7 and 14 days postmortem, respectively. None of the traits measured correlated significantly with 14‐day WBSF (P > 0.05). A three‐variable prediction equation that included 24‐hr calcium‐dependent protease (CDP) inhibitor activity, 0‐hr CDP‐I activity and 24‐hr cystatin activity accounted for 63% of the variation in 14‐day WBSF.