天然および養殖アユの品質に関する化学的研究-III : 含窒素エキス成分の季節変化

概要

論文の詳細を見る
A seasonal variation of the content of nitrogenous constituents in the extracts from wild and cultured ayu (sweet smelt), caught monthly from May to November, was studied. The amount of nonprotein nitrogen in the muscle of the wild ayu increased in August and that of the cultured ayu, in September. Of the free amino acids and related compounds determined, high levels of glycine, alanine, histidine, lysine, taurine, and anserine were found in the muscles of both types of ayu: the amounts of glycine, proline, and histidine of the wild ayu decreased gradually during the growth from summer to autumn, while the level of taurine of the cultured ayu showed a marked change in the above period. The creatine content in the muscles of both types of ayu increased with the growth of the fish, and that in the viscera varied considerably in the autumn. The seasonal variation of these nitrogenous constituents differed with different tissues and sex, and the variation in wild ayu seemed to be greater than that of the cultured one. There was a discussion on the taste of the ayu in relation to the distribution of nitrogenous constituents.