Extractive Components of Dried Skipjack

Taste Active Components of Dried Skipjack Part I

Abstract

The dried skipjack has widely been used from olden times in Japan to prepare sto ck. A principal taste-active component was already identified as IMP, but the contribu tion of other components to its characteristic taste is still obscure. In order to identify the taste-active components by the omission test using a synthetic extract, the hot-water extract of dried skipjack was first analyzed for free and combined amino acids, nucleotides and related compounds, other nitrogenous compounds, organic acids, sugars and inorganic ions. Large amounts of histidine and anserine were detected and the sum of both components reached about 86% of the sum of free amino acids and imidazole dipeptides. After acid hy drolysis of the extract, the content of free amino acids increased remarkably, indicating the occurrence of a considerable amount of oligopeptides. The levels of IMP, creatine and creatinine were also very high. More than 98% of the extractive nitrogen was accounted for by these nitrogenous constituents. Lactic acid was predominant among the detected organic acids, while sugar components were fairly low in amount. As for inorganic ions, Cl<^-, K<⁺, PO₄ ^3-and Na⁺ were major components.