Lactic acid bacteria were isolated at the level of 106 in one gram of the dough using the isolation medium containing 20ppm of cycloheximide. There was no change in the bacterial count during dough-fermentation for 4 hours. Raw materials were investigated to demonstrate the source of many lactic acid bacteria found in bread-dough. As the result, respectable number of lactic acid bacteria were detected in compressed-yeast or active dry-yeast, which are added to bread-dough as fermentation

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... s. Lactic acid bacteria of 108 to 1010 cells were counted from each one gram of different 7 samples of compressed-yeast, and 102 to 106 cells from each one gram of 6 samples of active dry-yeast, of which two samples are domestic and the others are imported products. Lactic acid bacteria isolated from bread-dough and 13 samples of yeast-product were identified as Lactobacillus plantarum, Lactobacillus casei, Lactobacillus cellobiosus, Lactobacillus brevis, and Bacillus coagulans. Almost all lactic acid bacteria isolated from bread-dough and compressed-yeast samples had a strong bioaction, that is, ability of acid formation from glucose by fermentation. Therefore, it could be sufficiently considered that in a present bread lactic acid bacteria contributed to its flavor, taste and texture as well as yeast.