Proportion of Collagen Types I and III in Four Bovine Muscles Differing in Tenderness

Intramuscular collagen containing both endomysial and perimysial tissue was extracted from four bovine muscles, analyzed for collagen types I and III, and related to total muscle collagen and meat tenderness. Isolated collagen was digested with cyanogen bromide and the proportion of collagen types I and III determined from densitometric scans of peptides resolved by SDS‐PAGE. Total collagen was different (P<0.05) for each muscle. However, only the longissimus had more (P<0.05) type III collagen than did the biceps femoris, semimembranosus, and semitendinosus muscles. Percentage type III was correlated with sensory panel connective tissue amount (0.48) and overall tenderness (0.48) scores for the longissimus and biceps femoris muscles.