Subjective and objective evaluation of veal lean color

Because veal lean color continues to be a primary factor that determines veal carcass value and is typically assessed by subjective means, it is important to explore objective methods for color assessment. Objective and subjective evaluations of veal flank and breast lean color were compared as predictors of longissimus lean color at 24 h postmortem. One hundred fifty special-fed Holstein veal calves were Kosher-slaughtered with blood samples collected upon exsanguination and analyzed for hematocrit and hemoglobin content. Lean color was evaluated in the flank and breast at 0, 6, 12, and 24 h postmortem. Color of the longissimus was evaluated at 6 h, when possible, and at 24 h. A panel of three trained individuals used a 5-point color standard developed in the Netherlands to visually evaluate lean color. A Minolta Chromameter CR-300 was used to obtain L*, a*, and b* values. A plant employee assigned packer grades at slaughter. Temperature and pH were also measured at each time period. Hemoglobin was more highly correlated than hematocrit with colorimeter values. Hemoglobin levels correlated well with a* values of the flank at 0 h postmortem (r = 0.52) although the correlation declined at 24 h (r = 0.30). The correlation between packer grades and 24-h visual loin color was r = 0.41. Visual loin color at 24 h postmortem was selected as the predicted variable for regression analysis. Temperature and pH did not contribute significantly to any prediction equations. The equation using breast L*, a*, and b* values at 24 h postmortem to predict 24-h loin color gave a higher prediction coefficient (R2 = 0.44) than the corresponding equation using 0-h breast values (R2 = 0.28). Objective measurement of lean color may be useful in veal carcass grading because it is more precise than subjective methods and would allow for uniformity among processing plants.