The physicochemical properties of rice globulin gel containing fatty acid salts were investigated. The addition of sodium caprate or sodium laurate increased softness, water-holding ability and transparency of the gel. Sodium caprylate also increased water-holding ability of the gel. Effects of various reagents on solubilization of protein from heat-induced gel containing sodium caprate suggested non-covalent bonds among the protein molecules mainly contributed to the stability of rice globulin gel containing fatty acid salts. N-ethylmaleimide did not inhibit gel formation, indicating that the disulfide bonds were not very important to form the gel with fatty acid salts in contrary with the gel without them. Scanning electron microscopy showed that the transparent gel had a very fine and homogeneous network structure in the gel able to keep the high water-holding ability of the rice globulin gel with fatty acid salts.

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By changing the rice whiteness of milling, the palatability improvement of old grain rice was examined. (1) The palatability evaluation was carried out on old grain rice with 3 stage milling of whiteness. When whiteness was rising, palatability was raised and the score of the flavor analyzer was also increased. (2) The higher whiteness caused the higher viscosity and higher viscosity characteristic value in palatability evaluation. (3) The multiple regression formula was obtained from the 6 score of palatability evaluation as a purpose variable and each analytical data as explanation variable. (4) Principal component analysis was made on each criticism value and each score of palatability evaluation. The property which related to the palatability among the whiteness was revealed by the score and load quantity of the principal component.

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The reduction of old grain rice flavor by a aroma rice addition was examined. (1) The aroma rice have the obvious difference with a whiteness, protein content, amylose content and also score. (2) Three % and 1% of additions of aroma rice improve a proper quantity of flavor and reduce old grain rice flavor. (3) From the palatability evaluation, 3% addition of Hieri and Haginokaori, improve the old grain rice flavor. This fact coincided with reduction of strength of flavor. (4) By the principal component analysis of aroma of palatability evaluation and the flavor analyzer value, the effect of addition of aroma rice addition was classified.

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The applicability of thermoluminescence (TL) method to the detection of Japanese domestic potatoes was examined. Potatoes of nine different origins were exposed to gamma rays at 0 to 150Gy and the minerals separated from the potatoes were subjected to the TL measurements. The fading effects of TL emission intensity were also examined during the storage of post-irradiation period. The irradiated samples gave large intensity of TL signals compared with those of non-irradiated ones, and there were proportionalities in the intensity and the dose. The quantum yield of the TL emission for each unit weight and shape of glow curves were varied in the samples from different producing regions hence the irradiated samples were difficult to be detected by using those parameters. TL ratios obtained from the irradiated samples in all regions were 0.15-1.00 and those obtained from non-irradiated samples were less than 0.15. Therefore, the irradiated and non-irradiated samples can be distinguished by normalization (TL ratio). The signal intensity decreased with the storage time, and the reduction of signal was more rapidly observed in the sample stored under light condition than that in darkness. However, the TL ratio of the samples irradiated at 150Gy and stored for five months could be distinguished from those of non-irradiated samples. It was also possible to apply this method to the detection of the domestic potatoes which irradiated in a commercial facility and purchased at a local market.

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To clarify immunoregulatory activity of a chrysanthemum flower extract, the effect on immunoglobulin or cytokine production in mouse spleen lymphocytes was examined. When the lymphocytes were cultured with the extract, the IgA, IgG and IgM production was suppressed in the presence of the extract diluted with phosphate buffered saline by 9 fold. At lower concentrations, a weak stimulation of the IgM production was observed. In addition, significant suppression of IFN-γ production was observed in the 729-fold diluted extract. But was hardly detected in the 27-fold or less diluted solution. The significant suppression of IL-4 production was also observed in the 27-fold or more diluted solution during the 24hr culture, with slight effect after the 48hr culture. Gel filtration chromatography of the extract provided different fractions suppressing and facilitating the IFN-γ production. These results show that there were both suppression and facilitation factors of the cytokine production in the mouse spleen lymphocytes in the chrysanthemum flower extract.

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Lactobacillus sakei HS-1 was developed as a starter for Japanese pickles. In order to judge whether L. sakei HS-1 has an aptitude for probiotics, the tolerance against simulated digestive juice and the recovery from intake test of L. sakei HS-1 were experimented. In a stomach model test, L. sakei HS-1 was alive at pH 3.5 in MRS broth containing 0.32% pepsin. In an intestine model test, L. sakei HS-1 showed strong bile tolerance, the concentration of dehydrated fresh bile in which the growth of L. sakei HS-1 was inhibited was 8.4%. By the administration of fermented food prepared with L. sakei HS-1, many living cells of L. sakei HS-1 were found in the feces of a volunteer. These results suggest that L. sakei HS-1 reaches the intestines alive after ingestion and has a possibility of being a probiotic.

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Yucca (Yucca schidigera Roezl ex Ortgies) has been used as a food additive and an animal diet in Japan and USA. The extract from yucca is now utilized as an anti-food-deteriorating agent in Japan. In this study, the effects of lipids on antimicrobial activity of yucca were investigated. Antimicrobial activity of yucca was inhibited by free unsaturated fatty acids, palmitoleic acid, oleic acid and linoleic acid. On the other hand, saturated fatty acids (palmitic acid and stearic acid) and oils composed of unsaturated fatty acids (olive oil, soybean oil and egg lecithin) had no effect on the antimicrobial activity of yucca.

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