Optimization of Thickness and Maturation Period of Andong-Soju Nuruk for Fermentation of Andong-Soju

摘要

To support the fermentational superiority of Korean nuruks and maintain the various domestic nuruks, the optimal nuruk production of Andong-Soju, which was designated as an intangible cultural asset of Gyungsangbukdo province from 1987, was investigated. Different thickness of nuruks (2.2-5.5 cm) were manufactured based on traditional Andong-Soju nuruk method, while the size of round form of nuruk was set to 23 cm. During the 3 weeks maturation, changes of water content, weight, pH, brix, the amountof reducing sugar, saccharifying activity, viable cell and major microorganisms were determined, Also, ethanol fermentation abilities of the manufactured nuruks were evaluated using 20% glucose medium or 16% starch medium, respectively. Our results indicated that the production of high quality of Andong-Soju nuruk needs 4.0-5.5 cm thickness and 3 weeks maturation without extraneous yeast addition. These results would be applied to production of homogeneous, and high quality of Andong-Soju nuruk.