In order to study on the effects of Bacillus natto on the soybean paste used natto, there were determind the contents of total nitrogen, amino acid, ammonia-nitrogen, total acid, reducing sugar and proteolytic activity etc.
The results are summerized as follows;
1) Fermentation of natto paste were faster than koji paste and the fermentation period were sufficient in thirteen days.
2) The chemical components, color, taste and flavor of natto paste (added 15% natto) were excellent than the other soybean paste.
3) The contents of ammonia-nitrogen and amino acid of soybean paste were gradually increased during thirteen days in the fermentation, while total nitrogen contents were decreased.
4) After thirteen days of the fermentation, the contents of amino acid were decreased.
5) The contents of amino acid of natto paste were much more those of koji paste.
6) Total acid and reducing sugar contents indicated a rapid increased from nine to fifteen days during the fermentation, and a slower and decrease after fifteen days.
7) Total acid and reducing sugar contents of natto paste were somewhat higher than those of koji paste.
8) No significant difference was observed in the contents of reducing sugar and total acid according to the amount of natto added.
9) The contents of reducing sugar and amino acid were proportional to the proteolytic activity.
10) A flood soybean paste may be produced by adding 15% natto to the raw material in thirteen days of the fermentation.
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