INFLUENCE OF THE PROCESSING CONDITIONS OF IBERIAN HAM ON PROTEOLYSIS DURING RIPENING

Non-protein nitrogen and its fractions (peptides, amino acids and vola tile basic nitrogen) were determined in biceps femoris and semimembran osus muscles of two homogeneous groups of Iberian dry-cured ham in dif ferent stages of maturation, and ripened in two different factories un der different environmental conditions. A progressive increase in non- protein nitrogen was observed during ripening in all groups, being esp ecially intense during the drying stage, when the temperature was the highest during maturation. During the first stages of processing, the proportion of peptides and free amino acids remained similar while fre e amino acids increased more markedly from the drying stage, represent ing the largest fraction at the end of the process. Volatile basic nit rogen was the least abundant fraction of non-protein nitrogen during r ipening. Hams kept at higher temperature during longer periods, and wi th lower salt content, produced larger amounts of all three fractions of non-protein nitrogen in fully ripened dry-cured Iberian ham.