MUSCLE AND ADIPOSE-TISSUE AMINOPEPTIDASE ACTIVITIES IN RAW AND DRY-CURED HAM

Free amino acids have been analyzed in biceps femoris muscle and adipose tissue from raw and dry-cured ham. A high increase was observed for all amino acids except glutamine and taurine. Major increases were in glutamic acid, arginine, alanine, valine, leucine, and lysine. A survey of five aminopeptidase activities of muscle and adipose tissue from raw and dry-cured ham was performed by using 7-amino-4-methylcoumarin derivatives of five amino acids (Leu, Arg, Ala, Tyr and pGlu) as substrates. Optimum activity was found at neutral pH and around 37-degrees-C, except the leucyl hydrolyzing activity which was 45-degrees-C. High recoveries of activity (25-75%) were obtained in the dry-cured ham. These enzymes might be responsible for free amino acids increasing during dry-curing.