Abstract
In order to examine the change of the amount of total and free amino acids during “Natto” processing, eighteen amino acids were determined by microbiological analysis. The specimens were obtained from soybeans in raw material and three processing stages, i. e. steamed 8 hours' fermented and 16 hours' fermented (Natto) .
On the total amino acid contents of “Natto” processing, no marked change was observed except that arginine decreased on each stage. The ratios of amino acid liberation (values of free base % in total) of the both fermented stages were 4% at 8 hours and 11% at 16 hours. The ratios of each amino acid liberation were high in alanine, tryptophan and threonine and markedly low in aspartic acid, proline, cystine and serine.
