In an attempt to obtain new yeast strains for sake production, breeding was made with two red pigment-producing and malic acid highly producing strains originating from a cycloheximide-resistant yeast haploid strain, K-1001, by backcrossing with KM1. The amount of malic acid produced by the bred strain, Dp-5-2, was much, exceeding 3, 000ppm, and its proportion to all organic acids was 82%. The resulting sake by the strain was colored light red. Another bred strain, Dp-5-38, produced malic acid at a proportion of 78% to all organic acids. The color of the sake produced by this strain was dark red. Both of these strains showed low producing ability for succinic acid. The results of the small-scale production tests indicated that fermentation steps by these strains progressed somewhat slowly than that by K-1001. However, a characteristic, red sake with a fresh, sour taste was produced. The cultivation of the bred strains in media containing adenine sulfate showed the decrease in malic acid production, suggesting that the production might be relevant to the pathway of adenine synthesis.
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