The relationships between color and pigment composition in the peel and leaves of Citrus hassaku during maturation were studied. (1) Seasonal changes of the peel color were classified into the three stages. In the first stage the peel color is green due to the high chlorophyll content regardless of the carotenoid content. In the second stage the peel color changes from green to yellow, because of the drastic decrease of the chrolophyll content, even when the carotenoid content is at the minimum level. In the third stage, the peel color becomes yellow-orange due to the disappearance of chlorophyll and the increase of carotenoids. (2) During the first stage, among the catotenoids separated by TLC the content of Hydrocarbon (H) in the peel was the highest, and Diol (D) and Dioldiepoxide (DD) followed. The carotenoid pattern was named as H-D-DD type. Then it changed to D-H-DD soon, followed by D-DD-H and subsequently by DD-D-H in the second stage. In the final stage the pattern became DD-M (Monol)-D by way of DD-D-M. (3) The greenness of the leaves from autumn to winter was attributed to the high chlorophyll content (40-180mg/100g). The leaf's carotenoid pattern was constantly D-H-DD type except for being H-D-DD type in fresh verdure. It resembled the carotenoid pattern of the green peel.

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Egg-laying hens were raised in individual cages on the diets supplemented with soybean oil, coconut oil, lard or beef tallow for 50 days before slaughter. Thigh and breast muscles and skin separated from each hens were analyzed to investigate the influence of dietary fats on the fatty acid compositions and on the cholesterol contents of chicken tissues. The total lipids of skin and muscles from hens fed on soybean oil contained the largest amount of 18:2 acid among those from hens fed on experimental diets, and had less 18:1 acid than the lipids of lard or tallow feeding groups. Significant amounts of 12:0 and 14:0 acids and less 18:1 and 18:2 acids were found in total and neutral lipids of the coconut oil feeding group compared to the other diet groups. Although the lard feeding group had a tendency to contain more 16:1 and 18:2 acids and less 18:0 acid than the tallow group in total and neutral lipid fractions, the fatty acid compositions of these groups were appreciably similar. The effect of dietary fats on fatty acid composition was more distinct in skin than in muscle lipids, and phospholipid fractions of muscles showed comparatively similar fatty acid composition on the feeding of each experimental diets to hens. Total cholesterol contents of skin, thigh and breast muscles did not significantly differ due to the dietary fats in respective tissues, but significant difference was found in cholesterol levels of chicken among the above-mentioned tissues. The average total cholesterol contents of skin, thigh and breast muscles were estimated to be 91, 66 and 51mg per 100g fresh tissue, respectively.

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The absorption spectra of an amylose-iodine color reaction solution at various pH values were taken over a broad region. The coloration of the amylose-iodine color reaction solution was stable until pH 9.82, but above this pH value the coloration rapidly began to be inhibited. At pH 10.88, the coloration was completely inhibited. At this juncture, it was observed that the amount of the triiode ion, I-3, in the reaction solution decreased as the alkalinity increased. When the addition of iodine was increased, the inhibition due to alkali was proportionally reduced. Even under the acidic condition, when the amount of iodine was decreased, the same inhibition of color was observed as under the alkaline condition. The concentrations of the triiode ion were almost the same under both conditions when the inhibition of the coloration began to appear. From the above results, it is presumed that the inhibition of the amylose-iodine color reaction is caused by a decrease in the amount of the triiode ion needed for the formation of the amylose-iodine complex. This decrease is attributed to the effect of alkali on iodine.

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Many pharmacologically active compounds such as daidzin, daidzein, are contained in Puerariae root. But, these components have been discarded in the solution which are obtained in the course of manufacturing of kuzu starch from the root. Therefore, an isolation procedure of the isoflavones, puerarin, daidzin and daidzein, in the waste solution was studied. When the solution was applied to "Diaion HP-20" resin column washed with H₂O, then eluted with 70% MeOH, and finally with MeOH, the crude puerarin, daidzin and daidzein were effectively obtained.

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Trichoderma viride cellulase was immobilized on cyanogen bromide activated agarose beads (Sepharose CL-6B). Maximum amount of bound enzyme-protein was about 12mg per g of agarose gel. Using immobilized cellulase, the hydrolysate of cellulose was mainly glucose. The immobilized cellulase was more stable at pH 1.5-2.0, and its heat stability was also enhanced at acidic pH. Immobilized cellulase was repeatedly used for 20h at pH 3.75 and 20°C in hydrolysis of CMC, retaining 75% of the initial activity even after the fifth reaction. Immobilized cellulase was used in an up-flow bioreactor bubbling N₂-gas and half of the cellulose was hydrolysed in 140h at 50°C.

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This paper describes the chromatographic behavior of phospholipases from rice bran with different hydrophobic gels. Hydrophobic gels (ligand concentration of 20μmol/ml gel) were prepared by coupling of CN-Activated Sepharose 4B with alkylamines such as n-butylamine (C₄), n-hexylamine (C₆), n-octylamine (C₈), n-decylamine (C₁₀), n-dodecylamine (C₁₂) and n-hexadecylamine (C₁₆). Phos- pholipid acyl-hydrolase (PAHase), phospholipase C (PLase C) and phospholipase D (PLase D) did not show hydrophobic adsorption with C₄, C₆ and C₈-sepharose 4B. But above enzymes was ad- sorbed with C₁₀, C₁₂, C₁₆-sepharose 4B and PHAase was eluted with 0.5% β-cyclodextrin ( -CD), PLase C and PLase D were eluted with 0.5% β-CD containing 0.2M NaCl. The hydrophobic behaviour of phospholipases was compared by using C₁₀-sepharose 4B gel with different ligand concentrarion (19.8-2.9μmol/ml gel). PAHase and PLase D were eluted with 0.5% β-CD and 0.5% β-CD containing 0.2M NaCl from gels, respectively. PLase C activity was increased in the eluent (1.5M NaCl) with the decrease of ligand concentration and almost completely eluted from the gel with 1.5M NaCl when the ligand concentration was 5μmol/ml gel. The purification fold of PAHase, PLase C and PLase D with C₁₀-sepharose 4B having ligand concentration of 5μmol/ml gel, were 35, 11 and 1.2, respectively and the yields of these enzyme activities were 82, 80 and 26% respectively.

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In the studies on oxidative deterioration of deep frying oils for soy-bean curd, we investigated the degree of oxidative deterioration of deep frying oils which are used in factories. The effects of coagulant and moisture contained in soy-bean curd on the oxidative deterioration of deep frying oil were also studied. The following results were obtained. (1) Among fifty-one oils tested, fifteen of them showed the acid value (AV) more than 3. (2) After exchanging oil in the fryer to fresh one at five factories, time course of the oxidative deterioration of oils which were used for deep frying for soy-bean curd were monitored by AV and carbonyl value (CV) every day. AV reached 3 within 15±3 days after deep frying, and after that time it increased linearly with respect to frying time. On the other hand, although CV attained approximately 50meq/kg after 7 days in three factories, this value reached nearly 20meq/kg after 2 days in the other two factories. However, after that time, CV of both groups remained almost unchanged. (3) Moisture content of soy-bean curd manufactured with MgCl₂, CaSO₄ or CaCl₂ as coagulant was 81.55, 79.44 and 79.28%, respectively. Soy-bean curd coagulated with MgCl₂ promoted the highest oxidative deterioration of deep frying oil and followed by CaSO₄ and CaCl₂ in this order. (4) By using CaSO₄, two soy-bean curds having different moisture contents of 79.44 and 83.32% were prepared. The latter accelerated oxidative deterioration of frying oil more rapidly than the former.

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A rapid and simultaneous determination method of saccharin, benzoic acid, sorbic acid and six esters of p-hydroxybenzoic acid in liquid foods by HPLC using isocratic elution system, was developed. Liquid food sample was loaded on SEP-PAK C₁₈ cartridge in acidic condition, washed with water, eluted with methanol and filled up to 10ml with methanol as test solution. Saccharin, benzoic acid and sorbic acid (group A) in the test solution were simultaneously determined by HPLC using Zorbax C₈ column and methanol-phosphate buffer (1+3) mixture as mobile phase. Six esters of p-hydroxybenzoic acid (group B) in the same test solution were simultaneously determined by HP LC using Zorbax ODS column and ethanol-phosphate buffer (2+3) mixture as mobile phase. The recoveries of the test compounds from samples fortified at 100ppm were more than 95.5%, and the detection limit of them in sample was 5ppm by the proposed method.

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Changes in distribution of low molecular weight carbohydrates, polysaccharides and organic acids were followed in the mycelium and fruit-bodies of Hiratake mushroom (Pleurotus ostreatus) grown on a glucose-peptone medium. (1) The total free sugar content in mycelium during development was found in the range of 4.62-19.46% in stipes 8.26-22.32%, and in pilei 5.50-12.84% in dry materials, respectively, while the total sugar alcohol content in mycelium during it 0.84-5.13%, in stipes 2.99-3.79%, and in pilei 2.13-3.39% respectively. In this mushroom, trehalose, mannitol, glucose, fructose and arabitol were identified, and trehalose, and mannitol were found to be major among them. Trehalose and mannitol were supposed to function as the main translocate carbohydrate. (2) The content of polysaccharides in mycelium during development was found in the range of 47.92-55.56%, in stipes 46.78-48.54%, and in pilei 41.18-42.07% in dry materials, respectively. The four polysaccharide fraction contents, that is, hot alkali-soluble fraction, alkali-soluble, acid-insoluble fraction (S-glucan), formic acd-soluble fraction (R-glucan) and alkali-soluble, acid-soluble fraction, did not change during development. Acetic acid-soluble fraction predominated in the polysaccharide fractions of the mycelium, but was the minor constituent in fruit-bodies. Acetic acid-soluble fraction accumulated in mycelium was used as the major transient storage carbohydrate for fruit-body growth. Utilization of chitin in mycelium also occurred during development. (3) The organic acid content in myceium during development was found in the range of 0.82-2.16%, in stipes 4.97-5.18%, and in pilei 4.12-4.46% in dry materials, respectively. The organic acid contents in fruit-bodies were 1.97-2.40 times as much as those in mycelium. In this mushroom, elevein kinds of organic acids were identified, Pyroglutamic, malic, succinic and fumaric acids were found to be predominant in mycelium, and malic, citric, pyroglutamic, succinic and fumaric acids were found to be predominant in fruit-bodies. There were remarkable differences in the distribution patterns of their organic acid compositions among mycelium, stipes and pilei.

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Free amino acid, organic acid and color of 21 samples from commercial cooked curry were investigated. They were also described by sensory evaluation, to compare the relationship between chemical components and taste. (1) Free amino acid contents in commercial cooked-canned curries were remarkably different among samples. The ratio of glutamic acid to the total free amino acids ranged from 50 to 87%, and was also different among samples. Principal component analysis showed that the samples were classified into five groups based on the free amino acid content. (2) Total organic acid and each organic acid contents were different among samples. Main organic acids in samples were lactic acid, acetic acid, malic acid and citric acid. Principal component analysis showed that the samples could be classified into five groups according to the organic acid level. (3) The color of cooked curries were different, especially in lightness and saturation. (4) According to sensory evaluation, taste and color of 17 samples were different by 5% level of significance. The most desirable curry contained free amino acids and organic acids at proper ratio.

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