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The thermal resistance of the important microorganisms in takju. Korean traditional turbid alcoholic beverage, was measured and optimun heating time and temperature to achieve the commercial pasteurization of these microorganisms were examined. Most of the vegetative bacterial cells in takju were destroyed by heating at over 60℃, except for the spore forming organisms, which did not actively grow in takju after pasteurization. The important microorganisms for the quality deterioration of pasteurized takju were then appeared to be yeast and molds, and their thermal resistances were measured. The thermal resistances of these microorganisms changed greatly depending upon the heating method. The D values of yeast in takju were 3.5 min at 65℃ and 0.46 min at 80℃ in cap-tube, and 7.1 sec at 65℃ and 2.3 sec at 80℃ in a continuous coil heat exchanger. Those of molds were 2.7 min at 65℃ and 0.25 min at 80℃ in cap-tube, and 3 sec at 65℃ and $lt;l sec at 80℃ in the coil heat exchanger. The acidity and pH did not change at 30℃ for two weeks after pasteurization by heating in the coil heat exchanger at 65~C for 17 sec, but the viscosity increased slightly by the heat treatment. Significant differences in sensory quality, especially the formation of burnt smell and bitterness by heating takju for 12D of yeast at 70, 80 and 85℃, respectively, were observed and this resulted in the significant reduction in overall likeness of pasteurized takju. However, when the heating temperature was fixed to 80℃, the overall likeness of pasteurized takju did not affected significantly by the heating time ranging from 8D to 12D of yeast. It was concluded that the optimum pasteurization condition of takju in a continuous heat exchanger was heating at 80℃ for 23sec(l0D of yeast).
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