Factors Influencing Color of Dark Cutting Beef Muscle

Color of dark cutting beef rib muscle was measured as affected by treatment with rotenone or chilling in an oxygen rich atmosphere. Samples homogenized with the mitochondrial inhibitor, rotenone, or pH 5.0 buffer remained red for up to 1 hr. Control samples blended with water remained red when chilled but turned dark when held at room temperature. Thin slices of dark cutting beef muscle would turn red when chilled in air or oxygen to 3°C, or when chilled in oxygen to 14°C, but would turn dark when transferred from oxygen at 3°C to air at room temperature. Thus, dark cutting beef muscle will turn red if mitochondrial respiration is inhibited, allowing myoglobin at muscle surfaces to remain oxygenated.