The 'Saijo' persimmon fruit softens in a very short period of time after dry ice treatment for the removal of astringency. In order to lengthen the short shelf life, the effects of several kinds of deastringent and preservation methods were investigated : deastringent methods ; carbon dioxide (CO₂), nitrogen (N₂), continuous exposure and gradual reduction of CO₂ (CO₂ gradual reduction), dry ice and powder alcohol, preservation method ; sealed preservation in a plastic container after removal of astringency treatment by dry ice or powder alcohol. Ethylene production was inhibited by both 100% N₂ and CO₂ gradual reduction deastringency treatments compared to the CO₂ treatment. But the degree of fruit softening was not affected by either treatment. This suggests that it is necessary to develop a new method for removing astringency that can decrease ethylene production below a certain threshold in order to delay fruit softening. Both unsealed and sealed fruit in a plastic container softened in 5 days after dry ice treatment. Unsealed fruit following powder alcohol treatment for removal of astringency softened in 7 days and sealed fruit softened in 40 days. Increased shelf life was observed in the sealed preservation after powder alcohol treatment compared with the dry ice treatment. The reason may be due to the preventing water deficit in the container maintaining low ethylene levels. These results indicate that sealed preservation in the plastic container after powder alcohol treatment for removal of astringency is useful for preventing fruit softening caused by the deastringency treatment.

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Postharvest application of 35-90% ethanol is reported to remove astringency and improve sweetness of banana. In order to determine the specific pattern and localization of gene expression, banana fruits were treated with 60% ethanol and control and then the total RNA extracted from the banana was hybridized with the RNA probe of ACC synthase gene. The highest ACC synthase activity was observed at 6 days after the ethanol treatment, while the accumulation of MA-ACS 1 mRNA (encoding banana ACC synthase during ripening) was observed in 9 days after the same treatment. In this experiment, the date of highest ethylene production coincided with the date of highest ACC synthase activity. The expression of ACC synthase gene is considered to occur firstly in pulp and then it occur in the peel on the basis of the signal intensity by Northern blot analysis.

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This study evaluated the use of electrolyzed water generated by electrolysis of potassium chloride for spray treatment on leaf surfaces of mitsuba (Japanese honewort, Cryptotaenia japonica Hassk) in solution culture. Growth examination and composition analysis were carried out with a non-sprayed lot as a control lot. As a result, free amino acid and total phenolic content increased both in the lot sprayed with diluted electrolyzed alkaline water and in the chlorine-containing lot sprayed with a diluted mixture of electrolyzed alkaline and acidic water. When compared at the same nutrient solution concentration as the control lot, the above lots also showed promotion and increase in the stem length, fresh weight and dry weight as well as intensification of leaf color. The factor of these results is supposed to be the stress response to electrolyzed water spray which added to the osmotic pressure in the organism by accelerating the generation of free amino acid and phenolic substances to raise the component concentration in the organism. Also, the intensity of the imposed stress was found to depend on the concentration of electrolyzed alkaline water and chlorine content.

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The bread-making quality of two domestic flours, Hokushin and Haruyutaka, blended with Victoria INTA, an ES flour, and Harunoakebono, domestic strong flour, was investigated. The baking quality of Hokushin, representative middle-strong flour in Hokkaido, and Haruyutaka, semi-strong flour with preharvest sprouting damage, which is unsuitable domestic flours for bread production, were both improved by blending with Victoria INTA. The results were as follows : (1) With an appropriate blend of ES flour, it was proven that domestic flours with poor bread making quality could be improved and given properties for bread making that are generally attributed to foreign hard flours. (2) The estimation of specific loaf volume of bread made from blends of the flours in this experiment was possible with the following multiple-regressive equation ;X₁=0.157 X₂+0.251 X₃+ 2.38 (X₁ : specific loaf volume (ml/g); X₂ : protein content of flour (%), X₃ : breaking force of dough (N)). (3) Through analysis by the use of this equation, it was proven that the improvements of bread making quality by blending poor domestic flours with ES flour were principally due to the progress of physical property of the dough, an increase in the breaking force of the dough.

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To study a difference of isoflavone content in soybean among planting year, we measured its content in 15-varieties soybeans harvested at 2000 and 2001, and also assayed the difference of isoflavone content in crops from different planting area on 3-varieties beans, Suzuyutaka, Tachinagaha and Tohoku 126. Furthermore, we studied processing suitability for Tofu of Suzuyutaka, Tachinagaha, Fukuyutaka, Tohoku 126 (High isoflavone content soybean variety), Tohoku 135 (All seed lipoxygenase lacking variety) and Tohoku 139 (Low allergenic soybean variety). The following results were obtained. (1) Tohoku 126 variety contained isoflavone the most quantity among 15-variety soybeans harvested at both 2000 and 2001. (2) It was concluded that the 126 variety was the most high-yield among 3 varieties soybeans, Suzuyutaka, Tachinagaha and Tohoku 126 in cultivation test carried out at five planting area in Fukushima. In addition, the 126 variety contained isoflavone the most amount without reference to the planting area. (3) An extractive ratio of protein and solid matter in soy milk extracted from the 126 was the most highest as compared with those of the milk from 4 varieties soybeans Suzuyutaka, Tohoku 126, Tohoku 135 and Tohoku 139 and it was the same on soy milk yield. In addition, the Tofu made from the 126 was the most highest in the breaking stress. (4) It was found out that breaking stress of Tofu produced from the 139 variety was improved remarkably by using hulled soybean as the material bean in stead of whole soybean or processing with the nonheating squeezing method. (5) Momen tofu was produced Tohoku 126 had the most highest scores in sensory evaluation for feeling with a tongue and palatability than those confected from Suzuyutaka, Tachinagaha and Fukuyutaka.

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