Texture measurement and a natural scanning electron microscopic observation (×250) of commercial fish jelly products (kamaboko) were performed in order to investigate the relation between textural properties and microstructure of kamaboko. Results obtained were as follows; (1) A three-dimensional network structure was observed in broiled kamaboko (yakiita kamaboko, sample 1 and 2), but not in steamed kamaboko (sashimi kamaboko, sample 3 and 4) under a natural scanning electron microscope. A natural scanning electron microscopic observation of steamed kamaboko showed a flat structure. (2) The jelly strengths of sample 1 and 3, made by the same company, were higher than those of sample 2 and 4. The jelly strength was higher in the lower (board side) of kamaboko than in the upper of it in all samples. (3) A finer network structure was observed in sample 1 than in sample 2. A natural scanning electron microscopic observation of sample 3 showed a flatter structure than that of sample 4. (4) A finer network structure was observed in the lower of kamaboko than in the upper in broiled kamaboko. A microscopic observation of the lower of steamed kamaboko showed a flatter structure than that of the upper of it. From all results, it was suggested that a differences in the microstructure of kamaboko affects the textural properties.

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The network system for product traceability (VIPS) in which consumers can browse information about their purchased products was developed. The latest technology, the XML Web service was adopted to build the system. Web pages are dynamically created by the input of the identification (ID) number which appeared on the label of the product. Farmers can input their information, which are ID number, harvest date, their name and so on, into the data base by the Web service system. As an application of two-way communication among farmers and consumers, questionnaires and bulletin board on the web site were also implemented. In addition, substitutional browsing means like cellular phone is also supported. Analysis of access log on the web server revealed the access frequency based on time, date and area. Responses from consumers and farmers clearly showed that VIPS is useful not only to meet the consumer demands but also to give farmers an incentive.

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The effects of relative humidity and the conditions of shipping containers on the quality of eggplants harvested in evening were investigated. The weight loss of eggplants was suppressed and the hardness of eggplants was kept during storage at high humidity. Whereas, the precooling treatment was no significant effect on maintaining the quality of the eggplants. The shipping containers such as normal corrugated container with a polyethylene film packaging bag, a corrugated container with perforated polypropylene film packaging bags and a corrugated container with a polyethylene laminated liner were useful to keep high humidity at practical conditions. The quality of the eggplants was maintained better than for those harvested in the morning and packed in usual corrugated shipping containers with inner waxed paper packaging. It was demonstrated that a high humidity storage was more effective for suppression of the transpiration rate of eggplants rather than low temperature storage.

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Effects of a particle size and chemical components of ground sesame seeds on their physical properties were investigated. Roasted sesame seeds were grounded automatically for 5min, defatted and separated by size with six sieves (53-850μm). The fraction with a particle size less than 53μm was extracted in turn with ethyl acetate, water and 80% ethanol. These samples were mixed with sesame oil and measured for hardness and adhesiveness by a texturometer and flow characteristic by a viscometer.
From these results, the fraction less than 53μm was proved mainly responsible for the decrease in hardness and viscosity and the increase in adhesiveness. These changes were also induced remarkably when the 105μm fraction or the 53μm fraction was combined about 30% with the fraction less than 53μm.
It was shown that the interaction between protein and oil was comparatively weak, but polarity lipids and water-soluble components such as saccharides strengthened the interaction between the particles of ground sesame seeds.

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8-Hydroxydaidzein (8-OHD) and 8-hydroxygenistein (8-OHG) were isolated and chemically identified as main antioxidants in soy sauce (shoyu) called tamari. These o-dihydroxyisoflavone (ODI), which show significantly stronger antioxidative activities than those of daidzein and genistein, were considerably contained in the Kojis prepared for soy sauces of koikuchi and tamari type, which abundantly used soybeans for incubation with Aspergillus oryzae. 8-OHD and 8-OHG were also present in enough amounts to exhibit antioxidative activities in the koikuchi and tamari shoyu. In tamari, the ODI content was closely related to the additional water content in Moromi mashing. The ODI amounts in siro shoyu which made the wheat to be a main raw material were limited. The antioxidative activities of soy sauces with higher content of ODI were generally stronger than those of the others. There was a good correlation (r=0.959) between ODI contents and antioxidative activities. The amounts of 8-OHD and 8-OHG in soy sauce were not significantly decreased by heating in boiling water for 60 minutes. From these results, it was suggested that these ODI in soy sauce contribute to protect the oxidative deterioration during the brewing of shoyu and the storing of processed foods using it.

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The effect of plant origin lactic acid bacteria on antimutagenicity for humans was tested. Mutagenicity of urine during 24 hours and of feces during 10 days for 4 healthy adults (men non-smoking) were measured when burned beef administration. Then fermented milk prepared with Lactobacillus casei subsp. casei 327 which was isolated from rice, burned beef and milk were administered to 8 healthy adults (men non-smoking) and mutagenicity was measured. Mutagen in urine and feces was extracted using blue rayon method. Mutagenicity was analysed with the Ames test, using Salmonella typhimurium TA98 (with S9 mix). Six hours after eating burned beef, mutagenicity extracted from urine increased, then returned to the original level. Fecal mutagenicity increased after 1 day, then returned to the original level after about 4 days. When eating burned beef and fermented milk, urinary and fecal mutagenicity were almost the same as the original level and the mutagenicity significantly lowered compared to when burned beef was administered. When eating burned beef and drinking milk, urinary and fecal mutagenicity increased as it did when burned beef was administered alone. The number of Lactobacillus strain bacteria in feces significantly increased when fermented milk was administered. These results suggest that administering L. casei subsp. casei 327 suppresses urinary and fecal mutagenicity arising from eating burned beef.

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Nutrition, in combination with good taste, may be a key for foods to survival in tomorrow's dynamic market. Proso millet has a high nutritional quality but its process characteristics are very poor. The objective of this research was to determine the effect of roasting, microwave and heat-moisture treatments on physical properties of proso millet flour for its application to food. Roasting treatment increased polydispersity of proso millet flour and heat-moisture treatment decreased it. Color of untreated flour resulted in a^*, -4.5; b^*, 20.1; whiteness, -18. However, whiteness of the flour was increased to the range of 18-43 by any treatments. Roasting and microwave treatments in proportion to temperature and time the decreased the damaged starch content determined by the AACC method, but heat-moisture treatment increased it. All the flour showed A-type of X-ray diffraction patterns. Heat-moisture treatment caused a little reduction of the relative intensities of the peaks. Gelatinization temperatures of treated and non-treated flour were in the range of 73-75°C, heat-moisture treatment increased both the conclusion temperature and enthalpy change. Roasting, microwave and heat-moisture treatments increased peak, trough, fina viscosity, breakdown and setback in RVA viscograms. The peak viscosity of flour was increased with an increase in temperature and time on roasting and microwave treatments. Suggesting that this increase resulted from inactivation of α-amylase in proso millet flour by the treatments.

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Carotenoids such as β-carotene, a predominant vitamin A precursor, and lutein and chlorophylls in vegetables have been reported to have antioxidative activity and desmutagenicity. In this paper, we developed a simple and rapid method to measure the carotenoids and the chlorophylls in vegetables. We adopted a simple extraction method with acetone without solvent transfer or evaporation for the extraction of them from raw vegetables. When water was added to freeze-dried vegetables before homogenization, pigments were extracted with high yield. β- and α-Carotenes, lutein and chlorophylls-a and-b were separated by HPLC on an ODS reversed-phase column, using linear gradient elution of ethyl acetate and acetonitrile-water (9:1). The contents of them were not reduced when extracts were stored at -20°C for two weeks.

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An optimum solvent is described for analyzing total polyphenol contents by the procedure of Folin-Denis assay. We used water, ethanol, methanol, acetone or dimethyl sulfoxide (DMSO) as the extraction solvent for the polyphenol analysis of several food materials. All these solvents provided excellent calibration curves for (+)-catechin in the range of 62.5 to 1000μg/ml(r²=0.998-0.999). DMSO gave the highest value of total polyphenol contents compared to the other solvents. Therefore, DMSO was proved to be the best solvent for the extraction of polyphenols from food samples. This improved method can be applied to the analysis of polyphenol contents in other food samples.

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