After storage for several weeks at 0°C, 'Saijo' persimmons (Diospyros kaki Thunb.) were treated with ethylene to obtain soft-ripened fruit. Fruit cracking occurred during soft ripening. There was a significant positive correlation (r=0.707^*) between cold storage period and the ratio of the number of cracked persimmons to the total number of treated persimmons. Shallow cracks seemed to occur in linear groups on the cuticular layer but did not reach the pericarp. Most of them were seen along the ventral suture near the fruit apex. Ruptures occurred mostly on the lateral side of the fruit. The location of shallow cracks and ruptures on the fruit were considerably close, suggesting that the ruptures developed from the shallow cracks. The occurrence of ruptures was observed 2.0 to 4.5 days after the beginning of ethylene treatment. Ruptures elongated afterward and finally became 100-140mm long. Artificial deep injuries in the fruit significantly induced fruit cracking more effectively on the skin near the fruit apex than on the equatorial zone of the fruit. It was suggested that the development of shallow cracks during cold storage prior to ethylene treatment causes cracking.

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The effect of MA conditions under high humidity packaging on the occurrence of postharvest Kohansho and the quality attributes of stored 'Kiyomi' tangor (Citrus unshiu Marc. × C. sinensis Osb.) fruit was investigated. Modified atmosphere containing CO₂ concentrations less than or equal to 12% and O₂ concentrations more than or equal to 10% had no effect on the occurrence of Kohansho under high humidity conditions. However, the occurrence of Kohansho was accelerated when the CO₂ level accumulated to 14%. Under the condition that CO₂ levels are not too high and O₂ levels are not too low, maintenance of a high relative humidity surrounding the fruit is considered to be the main factor for packaging design to prevent Kohansho. Furthermore, excessive CO₂ levels (more than 8 %) induced fermentative metabolism, resulting in high ethanol levels. MA conditions had no significant effect on the quality attributes, including firmness, TSS, TA, TSS/TA ratio, and AA contents under the high humidity condition. These qualities were preserved during the storage period, probably resulting from the maintenance of a high relative humidity inside the package. As recommended storage conditions and packaging design guidelines, 'Kiyomi' fruit should be stored particularly under a high relative humidity and should not be exposed to high CO₂ levels (>8 %) and /or low O₂ levels (<5 %) to prevent Kohansho and preserve high quality.

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The effects of heat-moisture treatment on the digestibility and viscous characteristics of hard wheat flour and separated wheat starch were examined to obtain basic data and information on texture modifier materials in food. From SEM, starch granules of heat-moisture-treated wheat flour appeared to change so as to have a flattened shape and showed adherence to other starch granules. The protein content and moisture content were not changed by heat-moisture treatment. The rate of protein degradation by pronase and the solubility of flour proteins in 0.5 M sodium chloride and water were markedly lower for the heat-moisture-treated wheat flour than for untreated native flour. The heat-moisture-treated wheat flour and separated wheat starch showed distinct peak viscosities in particular, native and heat-moisture-treated starch showed considerable differences; in their pasting temperature and peak viscosity. The apparent activation energy of native wheat flour paste at 14.7 kJ /mol was greater than that of the heat-moisture-treated wheat flour paste at 13.4 kJ/mol. In terms of starch pastes, the apparent activation energy of the heat-moisture-treated starch sample was 10.5 kJ/ mol, whereas that of the native sample was 25.9 kJ/mol.

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We investigated flavonoid formation in UV-B (wavelengths below 300 nm removed) irradiated buckwheat sprouts and the differences among six cultivars. The results showed the following. (1) Under UV-B irradiation, the hypocotyl elongation of buckwheat sprouts was suppressed in all cultivars. (2) In buckwheat sprouts cultivated in the dark, anthocyanin and isovitexin contents were negligible; however, UV-B irradiation markedly increased these contents. (3) The contents of rutin, vitexin, orientin and homoorientin tended to increase with UV-B irradiation, though there were some differences among cultivars. We concluded that UV-B irradiation at wavelengths below 300 nm efficiently removes accumulated flavonoids in a variety of buckwheat sprout cultivars.

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