The effect of alternating current high electric field (HEF) on the quality of green yuzu fruit during storage was investigated. The fruit were packed in polyethylene bags (180×270mm, 0.03mmthickness) and exposed to HEF (105kV/m : 60min, 430kV/m : 20min, 430kV/m : 120min). After the treatments, they were stored in a dark room at 2, 10 and 30°C, respectively. The weight loss of the fruit, pH, titratable acidity and total soluble solid of the juice, surface color, firmness and chlorophyll content of the peel were monitored during the storage. The HEF treatment on yuzu fruit reduced the evaporation of water, and retarded degreening of peel as shown by L*, a*, b* values and chlorophyll content. The acidity in the juice of treated fruit was reduced as compared to that of the control.

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With regards to the flavor characteristic compounds of fresh sweet basil leaves, a method of scrubbing and extraction by un-heating was devised. Results of gas chromatographic analysis of the headspace gas obtained by the leaf scrubbing treatment with glass beads were compared with those of the essential oil or the headspace gas from the leaves heating at 40°C. The main components of the headspace gas from the leaf scrubbing were 1, 8-cineol, and few detected ingredients than the essential oil. The flavor of fresh basil leaves was composed of terpenes with low boiling point. The flavor characteristic compounds of sweet basil were mostly yielded at the flowering period.

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Most of family restaurants and other food service facilities operate a system involving bulk food preparation at their central kitchen followed by low-temperature distribution. This study simulated potential bacterial contamination in such food preparation or distribution process to evaluate the effect of disinfection immediately before food consumption. Fresh-cut cabbage was inoculated with Escherichia coli, stored at 5, 15, or 25°C, then treated with sodium hypochlorite solution or electrolyzed acidic water to evaluate the bactericidal effects. Consequently, at either temperature, it became difficult to reduce coliform bacterial count after 8 hours or less of storage following inoculation. This result shows that low-temperature distribution may control microbial growth to some degree, but subsequent disinfection will be difficult once bacterial contamination occurs.

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The parent strain A. oryzae A-59 produce unsaturated fatty acids extracellularly. Using an UV irradiation process on the conidium, it mutated and obtained the mutant U-4 that was proven to be superior in secretion. The secretion property of the mutant U-4 stabilized. The extracellular unsaturated fatty acids were not only triglyceride, but also diglyceride, monoglyceride and free fatty acid. The mutant U-4, when cultured with 3.0% palmitic acid, produced 17.4mg/g dry cell of unsaturated fatty acids extracellularly, which was approximately 1.8 times more than that of the parent strain. In addition, the accumulation of fatty acid increased as the C/N ratio of the medium went up. The extracellular production of unsaturated fatty acids was a maximum at the C/N ratio of 6.0.

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The changes of cell wall polysaccharides obtained from Ume (Japanese apricot, Prunus mume Sieb. et. Zucc.) fruit differing in stages of maturation and tissue zone was determined. The relationship between cell wall polysaccharide content and hardness of Ume fruit was also researched. Ume fruit softened more and more accompanying growth. Though citric acid content in the fruit skin reached over 3.5% at the first half of enlargement phase, that in the fruit flesh came up to nearly 3.5% at the latter half of the phase, showing a decline in calcium that seems to be binding to some polysaccharides, especially pectic substances in AIS (Alcohol insoluble substance) accompanying a decrease in amount of the substances. The content of pectic substances in the flesh sample decreased noticeably along with an increase of the solubility compared to that in the fruit skin. The cell wall polysaccharide level in the skin samples was in range between 3.81% and 5.35%, but that in flesh samples was from 1.26% to 2.24%. They exhibited a trend to decrease in accompaniment with maturity of the fruit. The ratio of pectic substances, hemicellulose and cellulose content in the skin sample showed little change during development, but the flesh increased in pectic substances ratio and decreased in cellulose ratio. From these reasults, it was presumed that the softening of Ume fruit during growth may be cell wall loosening due to changes in cell wall tissue caused by an increase in solubility of pectic substances and a decrease of cell wall polysaccharide content originating in a decline of calcium in AIS induced with increase in citric acid content.

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Many attempts have been done to improve the properties of proteins by the chemical modification. Some problems should be solved, however, are still remaining. It is not the most reasonable strategy to modify the proteins by some chemicals, especially, usage modified proteins as food additives or medicinal supplies. The harms in those modified proteins to humans and environments could not be ignored. To improve the proteins without any harm, accordingly, the protein-glycosylation induced by the Maillard reaction was proposed. In the developments of newly antimicrobial proteins, some glycosylated-proteins were prepared from the food origin proteins including hen egg-white lysozyme and bovine milk lactoferrin. These glycosylated-proteins showed the enhancements of enzyme activities, stabilities against acidities and alkalinities, tolerances to heat, and improvements of emulsifying properties. Furthermore, the glycosylated-proteins reveal the antimicrobial effects on the typical gramnegative bacteria. The antimicrobial effects were also observed in the natural cheeses without the inhibitions the ripening. These are explaining that the glycosylated-proteins could be applied as food preservatives. The high pressure (HP) treatment in the liquid phase was employed for the glycosylation of lysozyme. This new strategy succeeded in reduction the insolubilities of reactants and acceleration the reaction time. The global optimization, the random-centroid optimization program was introduced into the HP treatment to find the optimum condition for the glycosylation of lysozyme. The optimization for 5 factors was completed by only 20 experiments. One tenth of the lysozyme was glycosylated with dextran under the optimum condition.

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