Phospholipase C (phosphatidylcholine cholinephosphohydrolase EC 3.1.4.3) extracted from rice bran was purified by precipitation with (NH₄)₂ SO₄ and column chromatographies on n-decylamine-Sepharose 4B, DEAE-cellulose, TOYOPEARL HW-55F and polyacrylamide disc gel electrophoresis with an overall recovery of 1.4% and 357 fold increase in specific activity. The molecular weight and the isoelectric point of rice bran phospholipase C were estimated to be about 160000 and pH 4.3, respectively. The enzyme had optimum pH of 9.5 to 10.0 and showed the heighest enzyme activity at 70°C. The enzyme was stable over the pH rang of 7.0-11.0, below 70°C. The enzyme activity was strongly inactivated by EDTA and it again activated by the addtion of Co²⁺. Km and Vmax for p-nitrophenylphosphorylcholine of the enzyme were estimated to be 15.3×10^-3M and 4.6×10^-5M/min·mg, respectively.

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Phospholipase D (phosphatidylcholine phosphatidohydrolase, EC 3.1.4.4) extracted from rice bran was purified by precipitation with (NH₄)₂ SO₄ and column chromatographies on n-decylamineSepharose 4B, DEAE-cellulose, Chromatofocusing and TOYOPEARL HW-55F with an overall recovery of 2.3% and 305-fold increase in specific activity. The molecular weight and the isoelectric point of rice bran phospholipase D were estimated to be about 160000 and pH 4.9, respectively. The enzyme had optimum pH 5.5 and showed the heighest enzyme activty at 37°C. There was an obligatory requriement of calcium ion for phospholipase D activity. Forty mM calcium was essential for maximal activity. The enzyme activity was inactivated by Cu²⁺, Al³⁺, p-chlromercuribenzoic acid and monoiodoacetic acid. Km and Vmax for phosphatidylcholine of the enzyme were estimated to be 7.14 ×10^-3M and 2.2×10^-5M/min·mg, respectively.

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As for the manufacturing Adzuki raw ann (unsweetened Adzuki bean Jam), it is important to cook the beans, in boiling water to be homogeneously soften well enough for mashing. Special care should be taken to prevent cracking of the swollen beans, which is responsible to the decreasing yield of the ann, losing the inner material through the cracks. The cracks seems to be caused as a result of excessive swelling of the bean grains and promoted by vigorous motion in boiling water. A new improved method for the cooking was designed to limit the volume of cooked beans within 2.2 times of the volume of original raw beans. Yield and quality of Adzuki raw ann by the new and usual methods and the sames treated in boiling water for 90min were compared. The results were as follows: 1) The average yield of raw ann products was about 68.1% constantly, for 90min cooking of the new method, while 67.5% as the maximum for the usual one of 60min cooking, decreasing the values by increasing the cooking time. 2) The quality of raw ann made by these two methods which is boild for 90min in water, seems to be better in physical aspects than that of raw ann by the usual method.

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The simple method was developed for determining caffeine and catechines in infusion of tea by high performance liquid chromatography with gradient elution system. The infusion of model manufactured green, Oolong and black tea made by Yabukita variety were determined by HPLC for comparison of caffeine and catechines concentrations. The caffeine concentration in those infusion was not different but the catechines concentration was different as follows: green tea>Oolong tea≥Black tea. The concentration of catechins chinese and Taiwan Oolong tea infusion were lower than that in the green tea infusion. Caffeine and catechines components of commercial oolong tea bag and drinks were different from Oolong leaf tea, and those patern was similar to the roasted tea infusion. The concentration of catechines in those infusion were less than those of Chinese and Taiwan Oolong leaf tea.

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1) Lisbon lemon showed a minus value in Hunter's chromatic "a" value, for about one month after its color reached pale yellow. There was high correlation between "a" value and carotenoid content during increase of carotenoid, but not between the "a" value and Brix-acid ratio in the juice of either Yuzu or lemon. 2) The chlorophyll content in the Yuzu peel was high in the green stage and then diminished in the yellowish orange stage. In the case of the lemon, chlorophyll content was less than half of the Yuzu in the green stage, but small amount still remained during the pale yellow stage. 3) After the disappearance of chlorophyll, the carotenoid content of the Yuzu tended to rise sharply, reaching higher level than that in the green stage. The carotenoid level in the pale yellow stage of the lemon was lower than that in the green stage. 4) In the Yuzu peel during the green stage Diol (D) content was the highest, and then Hydrocarbon (H) and Diol Diepoxide (DD) followed. The carotenoid pattern was designated as D-H-DD type and this type was found in Hassaku leaves and peel in the green stage. The pattern changed to DD-D-DM (Diol Monoepoxide) and then to DD-M (Monol)-D type followed by DD-M-DM type in Yuzu. The lemon peel showed a consistent H-D-DD type while the peel color was green. The type was found in the fresh verdure of the Hassaku leaves and peel. It then changed from H-DD-D to H-M-DD and finally to M-H-DD in the lemon peel.

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From the view point of utilization of kiwifruit (Actinidia Chinensis Planch.) protease for food, fundamental study was performed. Proteolytic activity extracted from fresh kiwifruit was compared with those from fig, pineapple and papaya fruits and the activity was found to be a little lower than those from fig and pineapple, but slightly higher than that from papaya. Proteolytic activity from kiwifruit increased in the course of fruit ripening. The activity in core was about 17% of that in Pericarp. When the crude enzyme solution was kept for 24h at 20°C, 4°C and -20°C, respectively, substantial loss of activity was not observed at 4°C and -20°C. On the other hand, about 30% of initial activity was lost at 20°C. When the crude enzyme solution was kept at -20°C for a long term, activity was stable and decreased gradually to a level of 75% of initial one after three months. When lyophilized powder of the fruit was stored in a desiccator at 20°C, the activity was relatively stable and there remained 80% activity even after stored for one month under this conditions. Crude enzyme had an optimal pH at 4.2. It was stable after heating for 5min at 50°C but unstable at 60°C. Crude enzyme showed a high level of caseinolytic and gelatinolytic activity, and digested cuttlefish and sasami well at 12°C for 24h.

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A high performance liquid chromatographic method (HPLC) was developed for the determination of organic acids (oxalic, tartaric, formic, α-ketoglutaric, lactic, acetic, citric, pyroglutamic, succinic and fumaric) in edible mushrooms. Organic acids were extracted with hot water. The solution was applied to a DEAE-sephadex A-25 column (borate type 20mm i.d.×50mm). The column was washed with 100ml of water, and organic acids were eluted with 0.1N hydrochloric acid. Organic acids were separated by HPLC on a column packed with KC-811 (8mm i.d.×300mm) by using 0.1% phosphoric acid solution as a mobile phase, and on a column packed with ULTRON N-C₁₈ (4.6mm i.d.×50mm) by using 0.1M potassium phosphate, monobasic, solution (pH 2.2) as a mobile phase with detection at 210nm. The recoveries of organic acids on DEAE column chromatography at levels of 75 to 1000μg were in the range from 80% to 110%. By using this method six commercial samples were analyzed. Eleven kinds of organic acids were identified. There were remarkable differences in the distribution patterns of organic acid compositions among the different species of edible mushroom.

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The effects of koji, yeasts and distillation methods on fragrance of rice-shochu were studied and evaluated by sensory tests. The components of fragrance of rice-shochu were influenced by both koji and yeasts, especially, the distillates using sake-yeast contained much larger amount of n-propanol, iso-amyl acetate, ethyl caprylate and ethyl caprate than those using shochu-yeast. The amount of ethyl esters of higher fatty acid reduced by usual distillation, vacuume distillation and vacuume distillation of filtered mash in the order named. According to sensory test, it was clear that the distillates by vacuume distillation had better flavour and taste and was evaluated as better than the others.

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In order to prolong the shelf-life of lizard fish meat, effects of removal of trimethylamine oxide (TMAO) from the meat by leaching and storage temperature were studied. TMAO in the nonleached minced meat was converted into formaldehyde (FA) and dimethylamine (DMA) rapidly during ice storage, while viscosity of meat sol and salt-soluble protein extractability (SSP ext.) decreased rapidly. TMAO in the minced meat was almost washed out by two or three times leaching with 4 volumes of leaching solutions to the meat weight. The leached minced meat could keep high viscosity of meat sol in ice storage for a long time. In -10--20°C storage, viscosity of meat sol in the non-leached and leached minced meat decreased because of freezing denaturation of SSP. The production of FA in the non-leached minced meat was much more in ice storage than in -10°C storage. In -80--60°C storage, both non-leached and leached minced meat could keep highviscosity of meat sol.

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