Prevention of Putrefactive Fermentation by Using Sound Tane-Moronzi and Pressed Azvamori No.1 Yeast

Abstract

Comparing with the putrefactive tane-moromi, the sound tane-moromi contained higher concentration of alcohol, higher value of the Nihonshudo (specific gravity of moromi) and less reducing sugar and amino acids. In addition the fragrance of the sound tane-moromi was better than the putrefactive one.
Of the low-boiling compounds, less acetaldehyde and much fusel alcohols were found in the sound tane-moromi. It contained isoamyl acetate which was not found in the putrefactive tane-moromi.
From the view point of practice, the pressed yeast method (use of pressed yeast for fermentation instead of conventional tane-moromi) is very useful. Then the constituents of pressed awamori No.1 yeast were analyzed: it contained 72. 5% of water, it was dark-brown and clayey and 1. 76×10¹⁰cells were contained in one g.
No significant difference was observed in the quality and the yield of awamori between the sound tane-moromi method (use of the sound tane-moromi for fermentation instead of conventional tanemoromi) and pressed yeast method. Furthermore, the putrefactive fermentation was prevented using these two methods.