- Volume 29 Issue 3
Yeast strains useful for the production of wine using mandarine orange, Citrus unshiu, as a main substrate were screened, and their primary ability to decompose citric acid that affects directly wine quality was investigated. Total eleven strains were selected for brewing orange wine. Five wild strains were from soil-based collections and identified: four of them were Saccharomyces cerevisiae and one of them was S. ellipsoideus. The rest of six strains were from among eighteen laboratory strains: three of them were S. cerevisiae, and the other three were S. coreanus, S. uvarum, and S. sake. Two strains of S. cerevisiae out of these selections were chosen and their decomposition of citric acid was investigated. Citric acid was not utilized as sole carbon source for cellular growth. However, when both citric acid and glucose were added together as carbon sources, decrease of citric acid concentration was observed after incubation. Shaking incubation was more effective for the reduction of citric acid than standing incubation. Utilization of citric acid did not contribute to the increase of ethanol concentration during fermentation. On the other hand, it appeared that citric acid caused partial inhibition of cellular growth of the yeasts.
yeast;orange wine;citric acid;decomposition