A high pressure ohmic heating process was used to cook Indica, Japonica, Koshihikari and glutinous rice. The physical properties of the cooked rice were measured with a compression tester, a differential scanning calorimeter (DSC), a color meter and a rapid viscometer. We found that when Indica rice was heated to over 120°C, it became softer and stickier so that the physical properties became closer to those of Japonica rice cooked using a traditional rice cooker. Whereas, the other three kinds of rice showed little change when the high temperature heating. We estimated that the difference was due to the high amylose content of Indica rice which undergoes a structural change when heated to more than 120°C due to the evidence from the DSC and rapid visco tests. The color change in glutinous rice was larger than in the other rice varieties. We concluded that the high temperature heating using high-pressure ohmic heating produces an improvement in the texture of Indica rice which has high amylose content.

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The purpose of this study is to evaluate the stabilization effects of sucrose, glycerol and trehalose on Hb as a representative of hemeprotein during freezing. The indicators were the amount of precipitate of the denatured protein, metHb formation by oxidation and Hill constant derived from the oxygen binding ability. The results obtained were as follows: The amount of the denatured precipitate was 3.6%, and metHb was 51% in control Hb at seventh month of freezing. The oxyHb-pO₂curve tended to be from the sigmoid to the hyperbola with increasing metHb. The Hill constant decreased from 3.0 to 1.4. No precipitate was observed in the samples containing more than 0.4% sucrose, glycerol or trehalose during 7 month's freezing. On addition of sucrose and glycerol of more than 1.6% or trehalose of 1.6-3.0%, the allosteric function of Hb could be kept even being frozen for a long-term. From this study, it is clear that sucrose, glycerol and trehalose have stabilization effects on hemeproteins. The mechanism was suggested in which the carbohydrates selectively form a pseudo-hydrated layer with surface water surrounding protein and stabilize the tertiary structure of hemeprotein molecule, resulting in protection against heme oxidation.

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It has been known that a kind of brewed rice vinegar (kurosu), which is produced mainly in Kyushu area by the traditional method, has a variety of physiological activities in vitro and in vivo. For example, kurosu has activities for improving blood parameters including blood pressure, total cholesterol value, blood fluidity of red blood cells and white blood cells. However, the chemical substance that execute these activities has not been identified. In this paper, we extracted the chemical substance responsible for fluidity of white blood cells in vitro by using a micro-channel flow tester for evaluating blood fluidity. As results of NMR and MS analyses, it was identified as histamine.

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By a method measuring the total ATP (Adenosine Tri-phosphate) cleanness of products through the procession of meat processing instruments was evaluated. This method was much more sensitive in detecting contamination sources (food residual dregs and microorganisms) than the conventional method, providing a useful contamination index. Because of rapidity and simplicity, the method is suitable for monitoring HACCP (Hazard Analysis Critical Control Point) system and for applying to job sites due to the easier maintenance of PP (Prerequisite Programs). Furthermore, it is effective in drawing up SSOP (Sanitation Standard Operating Procedures).

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The trend in seasonality in fresh vegetable and fresh fruit consumption was analyzed by the empirical Bayes smoothing method, using the data from Annual Reports on "The family income and expenditure survey" (1975-1995). The trend of yearly round consumption ceased or declined in many species of fresh vegetables, compared with the results obtained in the previous analysis (1963-1984). On the other hand, the trend of yearly round consumption was newly detected in some species of fresh fruits. The fact that peaches, persimmons and pears, which are the top three foods of the highest seasonality, showed the trend of year round consumption, characterizes the seasonal changes in fresh fruit consumption. Furthermore, as to three species of fresh vegetables, radishes, chinese cabbage and tomatoes, and three species of fresh fruits, mandarin oranges, apples and pears, features of the yearly trend of seasonality of their consumption were investigated in more detail by analyzing the yearly changes in monthly relative consumption, and the driving factors responsible for the changes of seasonality were discussed.

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The color changes of reimen under various conditions was investigated. When the temperature of heat pasteurizing process was higher above 100°C, L^* value was going down, but b^* value was going up suddenly, consequently the color of reimen was changed to the brownish color. The higher temperature during storage caused severe color change of reimen. This tendency was similar in heat sterilizing process. Storage under an anaerobic conditions, using oxygen absorber packaging, caused severe color change than an aerobic conditions. The effects were amplified under the high temperature. The color difference (ΔE^*_ab) value of reimen under the storage of anaerobic conditions were higher than that of aerobic conditions. After the storage of 6 month, the value at the storage temperature 2, 20 and 30°C were 0.9, 2.1 and 3.1 times respectively. It was considered that the both color change, caused by heat pasteurizing process and by storage of long period, took place by the same mechanism, as compared with the changing pattern of L^*a^*b^* values at different temperature. From the results, it was concluded that proper packaging and preserving condition were necessary to preserve reimen under good quality.

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The effects of low-oxygen atmosphere on the quality and ethanol and acetaldehyde formation of banana fruits were investigated. When mature green banana fruits were treated with 200ppm ethylene for 24 hours at 20°C, the ethanol formation in the banana fruits was accelerated and the contents of acetaldehyde and ethanol in the flesh tissues increased. In the banana fruits stored in 0 and 1% O₂ atmospheres, CO₂ production was suppressed and their skin color remained green, but the ethanol formation was accelerated, compared with those stored in air, so that ethanol accumulated. The accumulation of ethanol was seemed to cause off-flavor in those fruits kept in 0 and 1% 0₂atmospheres. Off-flavor in the banana fruits stored in 0% O₂ atmospheres was intensive. In the banana fruits stored in 2% O₂ atmospheres, CO₂ production was suppressed, remaining green in peel color of the fruits, and the ethanol formation in the fruits was also accelerated, though the contents of ethanol in their flesh tissues were lower than those stored in 0 and 1% O₂ atmospheres and maintained constant during storage.

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