CHANGES IN NITROGEN FRACTIONS AND FREE AMINO-ACIDS DURING RIPENING OFSPANISH DRIED BEEF CECINA

The changes in nitrogen fractions (total nonprotein nitrogen -NPN-, am ino acid nitrogen, peptide nitrogen and volatile basic nitrogen) and f ree amino acids during the ripening of ''cecina'' (a Spanish dried bee f product) were tracked The amount of fetal NPN, amino acid nitrogen a nd volatile basic nitrogen increased during processing, while peptide nitrogen decreased in the last stage. An increase was observed in all amino acids except taurine. In final product, the most abundant free a mino acids were leucine-isoleucine mixture, lysine and proline-methion ine mixture. Taking into account the concentrations of the most abunda nt amino acids detected in cecina and the taste threshold; described f or L-amino acids in water, it appears that several amino acids ie. lys ine, alanine, valine and glutamic acid, could contribute to the flavor of this meat product.