Chem. results on well-trimmed lean beef, canned beef sterile-cooked at 120° and 150°; lean control pork, canned pork sterile cooked at 120° and 135° indicated sterilization damage to the meat proteins were, resp. (on a dry weight basis): H2S 132.3, 125.0, 250.8, 77.4-120.8, 656-1277, and 482.7-1156 γ %; volatile organic bases (steam distillation) 46.3, 90.8, 217.3, 75.5-130.6, 194.1-202.8, and 168.1-226 mg. %; amino N, before hydrolysis 0.61, 0.40, 0.44, 0.50, 0.41, and 0.32; and after acid hydrolysis 9.84, 8.95, 9.61, 9.44, 9.09, and 9.05%; and amino acids (based on dry protein), methionine 2.53, 2.54, 2.16, -, -, and -; and tyrosine 3.74, 3.57, 3.66, 3.52, 3.25, and 3.33%.Destruction of methionine and accumulation of H2S were the main chem. indexes indicating the effect of the sterilizing cook on the meat proteins.Pork was more sensitive than beef.