We compared the storability under cold storage (1°C and 5°C) of on-tree alcohol-treated 'Hiratanenashi' persimmons individually packed in plastic film with that of persimmons treated with carbon dioxide after harvest to remove astringency. The persimmons stored at 1°C had better storability than those stored at 5°C. The time periods by which half the persimmons softened and lost their marketability for on-tree alcohol treatment and carbon dioxide treatment with storage at 1°C were approximately 140 and 170 days, respectively. The loss of flesh firmness of the persimmons treated with carbon dioxide gas during cold storage was faster than that of the on-tree alcohol-treated persimmons. The firmness of the on-tree alcohol-treated persimmons decreased only slightly during storage for three months. The peel color and soluble solid concentrations of the persimmons stored at both temperatures changed only slightly. When the persimmons stored for 65 days at 1°C or 5°C were moved to 20°C with or without plastic film, the persimmons without plastic film softened faster than those with plastic film, and those stored at 5°C softened earlier than those stored at 1°C. The shelf lives of the on-tree alcohol-treated and carbon dioxide-treated persimmons packed in plastic film after being moved to 20°C were about 5 and 10 days, respectively. From these results, the storability of on-tree alcohol-treated 'Hiratanenashi' persimmons packed in plastic film is approximately three months under cold storage.

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We investigated a brewing method of happou-shu using colored potato as a side source. Purple-colored wort was obtained when the sacchrification process was performed in a wort : colored potato ratio of 1 : 1. We extracted pigments having a purple color from steamed potato and the pigments were separately added before the primary fermentation stage of the brewing process of happou-shu. As a result, happou-shu having a purple color was successfully fermented. The present studies reveal that purple-colored potatoes are beneficial for giving happou-shu a puple color. Our data should be useful for developing a novel type of functional happou-shu or beer.

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In this study, we investigated the use of shoot length as an indicator of suitable steaming time for maintaining the total ascorbic acid (T-AsA) content of persimmon leaf tea during manufacture and preservation. We used persimmon leaves harvested in June. We determined their shoot length, and examined the effects of shoot length on leaf thickness and T-AsA content. The suitable steaming time for maintaining a high T-AsA content differed between leaves of different shoot lengths. The steaming times of foliating leaves (F-leaves), short leaves (S-leaves, 25-44cm), medium leaves (M-leaves, 45-64 cm), and long leaves (L-leaves, 65-85cm) were, respectively, 3, 5, 10, and 10 min. Results of the examination of different persimmon cultivars and individual picking times of the leaves imply that shoot length is a useful an indicator of suitable steaming treatment time.

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