Influence of Canadian beef quality grade and method of intramuscular connective tissue isolation on collagen characteristics of the bovine longissimus thoracis

Forty-eight bovine longissimus thoracis (LT) muscles, twelve from each Canada quality grade (Canada A, AA, AAA, and Prime) were used to test the hypotheses that intramuscular total collagen and collagen solubility decreased with increased quality grade and intramuscular fat, and that alkali isolation of intramuscular connective tissue (IMCT) does not reduce Ehrlich Chromogen (EC) or Pyridinoline (PYR) concentrations. Total collagen increased as intramuscular fat increased when estimated using lyophilized meat but did not when estimated using isolated IMCT. Beef quality grades and their concomitant intramuscular fat did not affect collagen heat solubility or mature collagen cross-link concentrations. Use of alkali for IMCT isolation did not degrade EC or PYR collagen cross-links, suggesting it is an excellent method for isolating IMCT for further characterization. The EC cross-link was most related to WBSF in the LT muscles from youthful cattle (< 30 months), confirming that EC is the most influential collagen cross-link on WBSF of low IMCT content muscles when cattle are young.