In order to investigate the relationship between taste and chemical components in cooked rice, the amounts of components in the whole and the outer layer of a milled rice kernel were measured. Three varieties, "Koshihikari", "Tomoyutaka" and "Rinx89" were chosen as the sample rices. The ratio of the amount in the outer layer to that in the whole kernel was calculated to show how the component is unevenly distributed. The sucrose accounted for 90% of the free sugar and the ratio in the outer layer was more than 60% in every variety of the rice. The ratio of fructose or glucose content in the outer layer was low and approximately 23%. "Tomoyutaka" as a whole kernel showed the highest in the amounts of total sugar, reducing sugar and free sugar among three varieties, however, the ratio of these sugars in the outer layer was the lowest in "Tomoyutaka". In all these three varieties, aspartic acid, glutamic acid, serine, and alanine were the main free amino acids and the sum of these four amino acids occupied 56-71% of the total amino acids in the whole, and 76-80% in the outer layer in every variety. In the whole kernel, the total amino acid content in "Tomoyutaka" was the highest among three varieties. On the other hand, in the outer layer, the total amino acid contents in "Tomoyutaka" and "Koshihikari" were almost the same. Panel members judged the difference and the preference of sweet taste, "umami", "unpleasantness" and "overall taste" of cooked sample rices. "Koshihikari" was judged to be significantly stronger in sweet taste and "umami", weaker in "unpleasantness" than the other sample rices. "Koshihikari" was also preferred in every taste to the others. "Tomoyutaka" and "Rinx89" were not significantly differentiated. We could not find any simple relations between the rating of the sensory test and the amount of the components.

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Influence of inert gases added to hydrogen on hydrogenation of soybean oil has been evaluated. Nitrogen, helium, and argon were employed as an inert gas mixed with hydrogen. Hydrogenation of soybean oil was conducted in a 12l loop reactor with reduced nickel catalyst. All the inert gases employed in this study influenced the reaction rate and trans isomer formation. When hydrogenation pressure was as high as 2.94×10⁵Pa (3kgf/cmcm²), the reaction was accelerated with increasing inert gas pressure. In the case of low hydrogen pressure, the reaction rate contrarily decreased with increasing inert gas pressure. Trans isomer formation was significantly depressed in conditions of high hydrogen pressure with high inert gas pressure. An experimental reaction rate equation taking inert gas pressure into account was derived to describe the influence of nitrogen gas added to hydrogen on hydrogenation of soybean oil. The constant of the equation showed good agreement with the experimental rate constant (k_RH), and the coefficient of determination (rr²) was 0.980 for hydrogenation of soybean oil. The experimental equation was applicable to hydrogenation of soybean oil with helium and argon gases as well.

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In our previous study, it was shown that tea catechins isomerized to its corresponding epimer by heating in infusion, suggesting that the analytical value of catechins in tea leaves closely depended upon the extraction temperature, time and media. For a simultaneous determination of caffeine and catechins by HPLC, a comparative study of extraction procedure to prevent isomerization of catechins was performed with conventional hot water and aqueous acetonitrile at an ambient temperature. Green tea was extracted with 100(w/v) times of cold water (20°C), hot water (80°C), acetonitrile (20°C), and aqueous acetonitrile (20°C) of different concentrations [75, 60, 50, 40 and 25%(v/v)]. It was found that catechins were slightly soluble in acetonitrile, but stable and maximum analytical value of catechins were obtained by the extraction of aqueous acetonitrile with the prevention of isomerization, and epimerization of catechins was proceeded during extraction with hot water which resulted in unstable analytical value. The proposed procedure was to extract green tea with aqueous acetonitrile (50%) at 20°C for 40min with stirring. By this procedure, maximum and stable analytical value of caffeine and catechins were obtained for the original concentrations in green tea. It was also found that at pH of extraction media above 6.0 green tea catechins isomerized to its corresponding epimer during extraction at 60°C for 3min, and browning of the infusion was accelerated.

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Binding property of aluminium ion to dietary fiber, polyphenol compounds and organic acids were measured by Eryochromcyanine R spectrophotometry or Chrome Azurol S spectrophotometry. Amounts of aluminium ion bound to 1g of soluble soybean dietary fiber isolated by modified Prosky method were determined as 21mg. Epigallocatechin gallate were bound to 1.6mg of aluminium. Citric acid showed the highest aluminium ion-binding ability and 1g of citric acid being bound to 44mg of aluminium. These results suggest that aluminium orally taken may be excreted as a complex with soluble dietary fiber or polyphenol compounds.

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The antioxidative activity of crude extract prepared from tamarind seed coat was studied. Tamarind seed coat extract showed high antioxidative activity and synergistic antioxidative effect with citric acid. The antioxidative activity of the extract was stable against the heat treatment at 100°C for 2h, and lower at pH 5.0 than at pH 3.0, 7.0 and 9.0. About 70% of the activity was remained even if treated at 100°C for 2h in the presence of 10% NaCl. The extract had antioxidative activity in two kinds of edible oils, lard and corn oil. In the lard, the addition of citric acid with the extract resulted in synergistic antioxidative action, however not showed inthe corn oil. From these results, tamarind seed coat extract might be used for natural antioxidants to lipid containing food.

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A nondestructive and rapid analytical method for determining the moisture content in dry sausage was examined using near infrared transmittance spectra with fiber optics. The downward peak at 972nm in the second derivative spectra became smaller with a decrease of the moisture content in dry sausage. It is suggested that 972nm is assigned to the second overtone of 0-H group. The highest multiple correlation coefficient of 0.996 was obtained in a linear regression equation that included two optical terms in the second derivative spectra at 972nm and 863nm, with a standard error of calibration (SEC) of 0.54%. The standard error of prediction (SEP) was 0.70% with a bias of -0.11%. Since there was a high correlation coefficient of 0.982 between water activity and moisture content of dry sausage, it may be possible to estimate the water activity from moisture contents determined by near infrared spectroscopy. Therefore, it is concluded that the method developed is useful for the process control of dry sausage.

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Calcium preparaticin was made from oyster shells by ohmicheating. It showed antimicrobial action in foods in a laboratory. Its applicability to actual food processing was investigated. Experiments were carried out at an ordinary food processing scale in factories. When the calcium preparation was added, viable bacterial cell number in foods decreased or didn't increase so much as the controls. In case of bean jam (an), antifungal action was observed even at less than 0.1% addition of the calcium preparation. When vegetables and meats were dipped into water solutions or suspensions of 0.1 to 1% the calcium preparation, antimicrobial action was observed. It was shown that the calcium preparation could be applicable to control microorganisms in actual food processing.

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Conger eel (Astroconger myriaster) is prepared with a seasoning sauce prior to broiling or boiling. The sauce is discarded due to contamination by foreign materials and microbiological populations. Plant scale regeneration of the waste sauce was attempted by the combination of pasteurization, hydrolysis, concentration, centrifugation and filtration. Suspended proteins and meat particles were hydrolyzed with proteases to nitrogenous substances and amino acids. Unhydrolyzed solids were removed by centrifugation and filtration. Bacterial and fungal populations were decreased by pasteurization. Microorganism growth was suppressed by concentrating the dry matter to 45% along with the addition of sodium chloride up to a final concentration of 15% by weight. Recycling of waste sauce provided a regenerated seasoning sauce acceptable for conger eel processing and a reduction in the burden of waste water treatment.

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The effect of the non-dialyzable extract of fresh spinach leaves on the induction of chromosomal aberrations by some carcinogens was examined in a cultured Chinese hamster lung cell line (CHL). The non-dialyzable fraction was found to suppress the induction of chromosomal aberrations such as chromatid exchanges and chromatid breaks by N-methyl-N'-nitro-N-nitrosoguanidine, hydrogen peroxide and mitomycin C.

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The egg shell ashed at 800°C (AES) were compared with Ca-carbonate, Ca-hydroxide, Ca-oxide and Ca-lactate concerning the hardness maintenance of brined ume fruit. As expected, the fruit without hardener softened, while the fruit with hardeners remained firm. But, the fruit with Ca-carbonate was less than 100% in the yield, markedly larger in AIS, less in NaCl content and larger in total acid. Ca amounts in fresh fruit and the fruit without hardener were strikingly less than that in the treated fruits. The fruit with hardeners was almost the same in Ca contents, though Ca in the fruit as Ca-carbonate was slightly less. By brining, the ratio of 0.05N HCl soluble pectin (HSP) to total pectin in ume fruit decreased, and both water soluble pectin (WSP) and 0.4% hexametaphosphate soluble pectin (HXSP) increased. However, change of HSP to WSP will be fairly suppressed with Ca-carbonate, and blocked with Ca-lactate, Ca-hydroxide, Ca-oxide and AES. Further, the fruit with Ca-hydroxide, Ca-oxide or AES was larger in the ratio of 0.05N NaOH soluble pectin (SSP). In the sarcocarp of fresh fruit, firm rectangular cells were observed clearly with scanning electron microscopic observation, but cells of the fruit without hardener were transformed to unclear flat shapes. Cells of the fruit with Ca-carbonate were observed as crushed flat shapes, but those in the fruit with Ca-lactate, Ca-hydroxide, Ca-oxide or AES were almost the same as those of the fresh fruit.

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