The yeasts in the soy sauce mash were isolated and identified, and they were classified by coloring with the treatment of TTC(2, 3, 5, triphenyltetrazolium chloride) agar and counted in process of time. The results obtained were as follows:
a) The number of ordinary and osmophilic yeasts in 1 ㎖. of the soy sauce mash showed a tendency to be increased from the mashing to the mature stages and to decrease in the aging stages: 127×10³ immediately after mashing, 86×10³ 1 month after, 356×10³ 3 months after, 1250×10³ 6 months after and 65×10³ 2 years after mashing in the case of ordinary yeasts, and 0 after mashing, 40×10³ 1 month after, 81×10³ 3 months after, 358×10³ 6 month after and 23×10³2 years after mashing in the case of osmophilic yeasts.
b) 50 strains of yeasts were isolated from the soy sauce mash optionally in process of fermentation period, and they were identified as 7 genera and 18 species: 10 strains of Saccharnmyces rouxii, 1 strain of Saccharomyces niarxianus, 3 strains of Saccharomyces rosei, 1 strain of Saccharomyces fermentati, 6 strains of Saccharamyces mellis, 1 strain of Saccharomyces acidifaciens, 1 strain of Saccharomyces pastori, 3 strains of Pichia polymorpha, 2 strains of Hansenula anomala, 1 strain of Hansenula saturnus, 2 strains of Hansenula suaveolens, 5 strains of Nadsonia fulvescens, 8 strains of Debaryomyces hasenii, 1 strain of Debaryomyces nicotianae, 1 strain of Debaryomyces kloeckeri, 2 strains of Torulopsis sake, 1 strain of Torulopsis holmii and 1 strain of Candida pelliculasa.
c) Distribution of yeasts according to the fermentation period was as follows:
i) Saccharomyces rouxii, Saccharomyces marxianus, Saccharoymces rosei, Pichia polymorpha, Debaryomyces hansenii, Torulopsis sake, Candida pelliculosa, Debaryomyces
nicotianae, Nadsonia fulvescens, Hansenula suaveolens and Hansenula saturnus were found in the early stages of fermentation.
ii) Saccharomyces rouxii, Saccharonzyces rosei, Saccharomyces fermentati, Saccharomyces mellis, Saccharomyces pastori, Hansenula anomala, Saccharomyces acidifaciens and Debaryomyces hansenii appeared in the mature stages.
iii) Saccharomyces rouxii, Saccharomyces mellis, Nadsonia fulvescenes, Dedaryomyces hansenii, Debaryomyces kloeckeri, Torulopsis sake and Torulopsis holmii were distributed in the aging stages.
d) TTC white yeasts were found in abundance in the early stages of fermentation and TTC red yeasts appeared more than 50 per cent in the mature and aging stages.
e) The yeasts belonging to Saccharomyces mellis and Saccharomyces pastori were classified as TTC red yeasts, Saccharomyces acidifaciens were reel pink, Hansenula saturnus Debaryomyces kloeckeri, and Torulopsis holmii were pink, Saccharomycess marxianus and Nadsonia fulvescens were white and the others were the same as the description in the previous report. Saccharomyces rouxii ware classified for the most part as TTC red yeasts, and while some of them were red pink.
f) Species of yeasts in the soy sauce mash were similar to those in the soy sauce koji, but the latter were not osmophilic and in the former case, the osmophilic yeasts were increased in process of fermentation period.
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