To investigate the properties that differ among potatoes with different specific gravities by examining the cell wall components of the plant's cell structure, each cell wall polysaccharide was fractionated from potatoes with different specific gravities, and the correlations of the yield and thermal changes with the physical properties of such potatoes were investigated. The yield of the cell wall hemicellulose fraction was about 1.1-fold higher and the yield of the cell wall cellulose fraction was about 1.4-fold higher in the potatoes with a low specific gravity than in thoes with a high specific gravity, which indicates the softness of fresh potatoes. On thermal analysis, the calories absorbed by the major cell wall component, the cellulose fraction, was about 5.4-fold higher in the potatoes with a low specific gravity than in those with a high specific gravity. The yield and thermal changes of the cell wall polysaccharides differed among the potatoes with different specific gravities. Therefore, the ratio and thermal change of cell wall polysaccharides markedly affect the processing characteristics of potatoes.

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The differences in texture parameters between fresh and steamed potatoes of two defferent varieties, Mayqueen and Danshaku imo, which are the two main varieties of potatoes produced in Japan were examined. Fresh samples of both varieties showed increases in hardness, cohesiveness and gumminess with increasing specific gravity. Steamed samples of both varieties showed decreses in all texture parameters with incresing specific gravity. A primary regression equation was computed to express the relationship between specific gravity and texture parameter. Samples of both varieties with identical specific gravities showed high binding strengths. Mayqueen showed a high viscoelasticity and a high resisitance to collapse. However, Mayqueen also showed a texture similar to that of Danshaku imo white using high-density potato samples, which showed no resistance. Potato thermal analysis of fresh potato samples showed a low density and a high heat capacity peak of the cell wall component in both varieties at 70-100°C. This indicates that a large amount of heat is necessary to change the properties of hypobaric samples of both varieties by steaming. It was surmised that the properties of Mayqueen being highly mucilaginous and having a high binding strength are the main reason a large amount of heat is necessary to change the physical properties of this variety by steaming.

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In an effort to determine the anthocyanin (AN) pigment yield during the maturation of pickled red cabbage, the determination of pH, acid content, salt level, absorbance, degree of browning and color tone and analysis by LC/MS and HPLC were conducted. The results indicate that the pickled red cabbage maturation method may be used in preparing AN pigments. (1) During the maturation of pickled red cabbage, a pH decrease accompanied an increase in acid content, and an increase in absorption rate was observed on days 5-9. No notable browning ensued and the cabbage's color tone became deep red, which progressively darkened with maturation. (2) The structures of red cabbage AN pigments were estimated to be as follows : P 1 : cyanidin [Cy] 3-O- (2-O-β-D-glucopyranosyl [Glc]) -β-D-Glc] -5-O- (β-D-Glc)]; P 6 : [Cy-3-O- (2-O- (6-O-p-coumaryl [pC] -β-D-Glc)) -5-O- (β-D-Glc)]; P 7 : [Cy-3-O- (2-O- (2-O-sinapyl [Si] -β-D-Glc)) -5-O- (β-D-Glc)]; P 9 : [Cy-3-O- (6-O-pC-2-O- (2-O-Si-β-D-Glc)) - (5-O- (β-D-Glc)); P 10 : [Cy-3-O- (6-O-ferulyl [Fr] -2-O- (2-O-Si-β-D-Glc)) -5-O- (β-D-Glc)]; and P 11 : [Cy-3-O- (6-O-Si-2-O- (2-O-Si-β-D-Glc)) -5-O- (β-D-Glc)]. (3) The yield of total AN pigments was highest on days 5-9 of the maturation of pickled red cabbage. Among the red cabbage AN pigments, P 1, a nonacylated AN, had the highest yield, which remained unchanged from days 0 through 21. However, the yields of P 6 and P 7, which are acylated AN pigments, increased up to day 9. These three pigments comprised the principal AN pigments of pickled red cabbage.

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The effect of 1-methylcyclopropene (1-MCP) treatment on the postharvest quality of sudachi (Citrus sudachi hort. ex Shirai) fruit was investigated with the aim of prolonging their storage period. Sudachi fruit were treated with 1-MCP at various concentrations of 0, 0.01, 0.1, 0.5 and 1.0μl·l^-1 for 6, 12 or 24 hr at 20°C and then stored in the dark at 20°C. The treatment with 0.1μl·l^-1 1-MCP for 24 hr was the most effective in delaying the degreening of sudachi fruit. This treatment with 0.1μl·l^-1 1-MCP did not induce peel browning, weight loss and internal quality degradation in sudachi fruit. On the other hand, at higher concentrations (i.e., 0.5 and 1. 0μl·l^-1), 1-MCP had little effect on the delay of degreening and induced undesirable responses, such as peel browning and weight loss. We suggest that appropriate 1-MCP treatment as postharvest treatment could be applied for commercial use to the maintenance of the marketable green color of sudachi fruit.

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In this study, we carried out various tests on the detachment of a thick omelet from a frying pan to develop vegetable oil by supplementation with soy bean lecithin. The results are as following. (1) A thick omelet was not detached from an aluminum pan with corn oil. It was necessary to use parting oil in the detachment. The adequate volume of parting oil for the detachment was 2% of the volume of egg mixture. (2) The detachment was good when the temperature range of the egg mixture was 10-30°C. At 100°C, the temperature of the aluminum pan used in cooking was slightly higher than over 110°C. (3) The detachment was poor when the pH of egg mixture was low. (4) The optimum volume of soybean lecithin for good detachment was 3% of the volume of parting oil. (5) An effective good supplement for the detachment was waxy corn starch, which is better than potato starch. The addition of such starch at 2% of the volume of the egg mixture had no adverse effect on taste. (6) The parting oil developed was also suitable for the detachment of takoyaki.

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In this research, we studied the detachment of steamed Chinese noodles from each other using a type of vegetable oil (noodle parting oil) supplemented with soybean lecithin. When steamed Chinese noodles are sold, they stick to each other, and form dumplings. Therefore, a noodle-picking machine should use some parting oil in cooking Chinese noodles. We developed a parting oil that facilitates picking noodles. The following are the results of our study. (1) The parting oil used in the detachment test contained soybean lecithin and was turbid. We determined the cause of the turbid it. We found that turbidity occurs when the quantity of the emulsifying agent increases right after manufacturing, there by leading to an increase in surface moisture content and the transformation of the emulsifying agent to an emulsion. The optimum quantity of emulsifying agent to prevent the formation of an emulsion was 0.5% of the quantity of oil, and that of vegetable oil was 2% of the quantity of noodles. (2) It was proven that the parting oil developed for steamed Chinese noodles does not affect the increase and decrease in the general bacterial count in the storage test. (3) There was a small weight variation due to moisture loss between the oil-free and corn oil because the parting oil for noodles was uniformly applied to the surface of the noodles. (4) It was proven that the oxidation stability differs with oil type.

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In this study, we compared the distribution of corn oil and that of rice cooking oil before and after cooking rice, and the hourly variation in the texture of cooked rice to develop a rice cooking oil. The following are the results of this study. (1) Rice cooking oil mixed with soybean lecithin uniformly dispersed better than corn oil in a pan. (2) Rice cooking oil also uniformly dispersed even in large-scale cooking better than corn oil in an iron pot and in a pan. (3) The variation in the texture of cooked rice supplemented with rice cooking oil with aging was less than that of the nonsupplemented rice the former also exhibited little moisture loss.

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