The relationship between the activities of endogenous enzymes in milled rice and the accumulation of chemical components in the rice grains during cooking was compared for five cultivars: Koshihikari, Nipponbare, Habutaemochi, Yumetoiro and jasmine rice. The effects of temperature on the accumulation of chemical components in grains of Nipponbare were similar to those of Koshihikari. Sugars, particularly glucose, in the rice grains accumulated during cooking with all cultivars. Amino acids accumulated much less than sugars. The hydrolytic activities of the endogenous enzymes for carbohydrates in the five cultivars were maximized at 60°C, while the proteolytic activities were weak under every condition. The gelatinization onset temperature of rice flour was 60-64°C for all the cultivars. The mechanism for the accumulation of chemical components during cooking by hydrolases in milled rice, as revealed for Koshihikari, was applicable to the various rice cultivars; around 60°C was the key temperature for substantial production of glucose by the endogenous enzymes in milled rice, and the amount of sugars in cooked rice depended mainly on the cooking conditions.

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The relationship between the activities of endogenous enzymes in milled rice and the accumulation of chemical components in the rice grains during cooking was compared for four milling yields of Koshihikari. Sugars, particularly glucose, in the rice grains accumulated during cooking for all milling yields, especially for the higher yields. Reducing sugars and amino acids accumulated more for lower milling yields than for the higher yields. A comparison the thermal dependence of the hydrolytic activities showed that the glucosidase activity at 60°C was characteristically high in 85% and 90% milled rice, although the amylase activity at 30°C and proteolytic activity at 40-60°C was relatively high in 95% and 100% milled rice. The gelatinization properties were similar for all milling yields. Although glucose accumulation in rice grains at 60°C is characteristic during cooking for all milling yields, the difference in behavior of endogenous enzymes between different milling yields may affect the accumulation of chemical components during rice cooking.

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The palatability and physicochemical properties of sake and miso stored in a snow room for four months were evaluated. The storage conditions during the four months were an average temperature of 1.7°C and stable relative humidity of 96.9%. A statistical analysis was performed to compare the palatability and physicochemical properties of the products stored in the snow room with those stored under control and custom conditions. The principal component scores, showed a large difference between the snow room and the control and custom conditions, the contribution of the first principal component being high for sake. Miso produced a plot with equal distance among the three conditions. The results for sake and miso suggest that aging by snow room storage had a positive influence on the color tone, acidity, taste, sweetness and flavour.

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The effect of parental instruction on the way that college students held chopsticks and their table manners was studied. The ways of holding chopsticks by 87 female college students were photographed and categorized into the traditional group (60.9%) and non-traditional group (39.1%). These non-traditional ways were sub-categorized into 6 types. The traditional group had received long-term instruction from their parents during their early childhood which led to traditional table manners for holding chopsticks. In contrast, the non-traditional group had received short-term instruction in the later stage of their childhood, showing the necessity for giving continuous instruction during early childhood. Compared with the non-traditional group, the traditional group were significantly (p < 0.05) more conscious of their table manners for using chopsticks and of the importance of having meals with the family. Both groups showed willingness to hand down the traditional way of using chopsticks.

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