RELATION BETWEEN THE FREE AMINO ACIDS, ANSERINE AND THE TOTAL VOLATILE BASIC NITROGEN PRODUCED IN MUSCLE OF HAKE (MERLUCCIUS MERLUCCIUS, L.) DURING ICED STORAGE

This work studied the development of free amino acids (FAAs) and dipeptide anserine as quality indices for gutted hake stored in ice for 25 days. The correlation of these compounds was determined with total volatile basic nitrogen (TVBN) which has been used as a quality index, for fish stored in ice. The most abundant free amino acids in hake muscle were found to be threonine, glycine, alanine, glutamic acid, β-alanine methylhistidine. lysine and the dipeptide, anserine. The only hydrophobic free ammo adds which exhibit significant differences (P<0.05) throughout storage was tryptophan. moreover, this amino acid exhibited a very high correlation (r=0.951) with TVBN. A significant decrease in anserine (P<0.05) correlated with the increases in 1-methylhistidine and β-alanine throughout storage. These changes also exhibited a very high correlation with TVBN. Therefore, 1-methylhistidine, β-alanine anserine and tryptophan could be used as quality parameters for hake stored in ice.