A method using gas chromatography (GC) after separation with bubbling was proposed for the microdetermination of sulfur dioxide in foods on the basis of GC method. Because the values of sulfur dioxide contents of foods were different depending upon the method using colorimetry after separation with bubbling (bubbling-cololimetric method) or GC method, this distiction was caused by difference of pretreatment of tested sample. On the proposed method, volatile aldehydes and other sulfur compounds interfered less intense than the original method. Good agreement was obtained between the values of sulfur dioxide contents by the proposed method and the bubbling-colorimetric method in various foods except for "wasabi" powder. The sulfur dioxide was detected in foods which was not added sulfur dioxide (containing other volatile sulfur compounds) by the proposed method and the GC method, and identified by GC-MS. By the proposed method, blank values from the foods which was not added sulfur dioxide were confirmed to be actually due to sulfur dioxide by bubbling-colorimetric method and modified RANKINE'S colorimetric method. The recoveries of sulfur dioxide from foods were 82.5%-101% at the level of 10ppm and the detection limit was 0.2ppm in the case of 5g of sample size.

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Six rough rices were obtained from the experimental plantings of high yielding rice plants in Japan. Two were domestic varieties; 'Arborio J-1' and 'Arborio J-10', and four were foreign varieties; 'Mitsuyo-23', 'Raikei', 'IR-24' and 'RP 9-3'. The characteristics and qualities of rice bran oils extracted from the above rice plants were examined, and compared with those from common Japanese rice plants. The combined percentage of oleic acid and linoleic acid was ca. 75%, but the ratio of the two acids was apparently different between common Japanese and foreign varieties. Tocopherol contents of foreign varieties were lower both in total tocopherol content and in α-tocopherol content than those of domestic and common Japanese varieties. There were some differences in tocopherol pattern among varieties. In foreign varieties tocotrienol was contained ca. 3.57 times more than that of tocopherol, and their major tocotrienol was γ-type (ca. 89%).

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Satsuma mandarin (Citrus unshiu Marc.) juice was packaged into the two kinds of pouchs (Polyethyleneterephthalate (PET)/Aluminum foil (Al)/High-density polyethylene (HDPE) and PET/Al/Polypropylene (CPP)) and the adsorption of volatiles on plastic films was investigated. Glassbottled juice was used as control and following results were obtained: (1) After 7 days of packaging distribution ratios (film/juice) of the volatiles in the PET/Al/HDPE pouch were 1.2-1.7 for terpene hydrocarbons, 0.65 for terpene aldehydes, 0.19-0.24 for terpene alcohols, respectively. (2) While the recoveries of terpene hydrocarbons from the juice packaged in the PET/Al/HDPE pouchs decreased continuously for 14 days. As to the PET/Al/CPP pouchs, the minimum recovery was marked after 7 days storage. The recoveries of linalool and citronellal from the juice in the PET/Al/CPP pouch increased only after 7 days storage. (3) The pulp in the juice suppressed the adsorption of aroma by plastic films. It was especially so high in the PET/Al/HDPE pouchs than in the PET/Al/CPP. When the juice with 4.4% pulp content was packaged in the PET/Al/HDPE pouch, the recovery of linalool from the juice was one and a half times higher than that of the control after 7 days storage.

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Production of radish seedling (Raphanus sativus L. var. longipinnatus L.H. Bailey cv. Tokinashi) which is called "Kaiware Daikon" is increasing recently in Japan. Effect of illumination intensity during cultivation on the quality of radish seedlings including ascorbic acid (AsA) content and its histochemical distribution and chlorophyl content was investigated to elucidate the optimum condition for illumination. Radish seedlings which had germinated previously in the dark at 25°C for 6 days were illuminated with different intensities ranging 0, 500, 2500, 5000 and 10000 luxes for 48 hours, respectively. (1) Elongation and thickening of the hypocotyl of radish seedlings were inhibited significantly by the illumination, while no significant difference in the average length and diameter of hypocotyl and average weight of seedlings was found among different intensities of illumination. (2) Illumination accelerated the hardening of the hypocotyl and the hardness was nearly in proportion to illumination intensity after 48 hours. (3) Ascorbic acid content in the cotyledon of seedlings continued to increase in proportion to intensity during illumination for 24 hours. Then, the content reached to a plateau in all plots. (4) Chlorophyl content in the cotyledon continued to increase during illumination with 500-10000 luxes for 48 hours. Increasing rate of chlorophyl content was proportional to illumination intensity. (5) A linear relationship was found between chlorophyl and AsA contents in the cotyledons of seedlings illuminated with different intensities. The correlation coefficient between chlorophyl and AsA contents was found to be +0.91. (6) Microscopic observation revealed that distribution of AsA was in the parenchyma cells of palisade and spongy tissues in cotyledon of seedlings in all plots. Much more abundant AsA was observed in the cells of palisade and spongy tissues in cotyledons of radish seedling illuminated with high intensity.

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This work was undertaken to determine the degree of retention in green cheese of nitrate added at the initiation of the cheese making process, and to observe the reduction of nitrate and the formation of nitrite in cheese during the ripening process. Furthermore, in order to understand whether Penicillium candidum inoculated in the manufacturing process as fungal starter are related to the reduction, the effects of microorganisms on the reduction of nitrate and formation of nitrite during ripening in cheese were evaluated. The results were as follows; (1) The retention ratio of nitrate added in the manufacturing process to the green cheese was approximately 7-8% for Gouda cheese and 13-15% for Camembert cheese. There was a close relation between the degree of retention of nitrate added and moisture contents in green Camembert and Gouda cheese. (2) It was found that nitrate reduction and nitrite formation or disappearance in Camembert cheese are more remarkable than those in Gouda and Blue cheese. In general, the maximum nitrite-forming time in Camembert cheese coincided with the time suitable to eat. (3) As a result of comparative experiments with P. candidum culture, it was ascertained that notable reduction of nitrate and nitrite in Camembert cheese during the ripening process may depend on nitrate and nitrite reducibilities derived from P. candidum starter inoculated at the initiation of ripening process.

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The changes of lipid and fatty acid composition in total lipids (TL), neutral lipids (NL), Glycolipids (GL) and phospholipids (PL) in "Hoshi-Gaki" (sun-dried persimmon, Diospyros kaki) during the processing were studied by means of column, thin-layer and gas-liquid chromatographies. Fresh astringent persimmon, "Anpo-Gaki" (sun-dried fruits for 30 days) and "Koro-Gaki" (Sun-dried fruits for 60 days) were used as samples. (1) The apparent content of TL increased (0.09→0.12→0.23%) during the process of sun-drying. (However substantially it decreased (0.73→0.47→0.33g per 100g of flesh by dry base)). (2) The triacylglycerol (TG) content decreased (24.2→20.0→14.5g), and the free fatty acid content in NL fraction increased (10.4→16.8→23.5%) due to the hydrolysis of TG by lypase. (3) Monogalactosyldiglycerides and sulfoquinovosyldiglycerides in GL fraction and phosphatidyl-N-methlethanolamines and phosphatidyl-N, N-dimethylethanolamines in PL fraction were not detected after 60 days of sun-drying process. (4) C 18:3 and C 16:1 acids decreased but C 16:0 acid increased in the drying process. C16:0 acid might be produced by the oxidation of unsaturated fatty acid.

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Relationship between sugar composition and sucrose hydrolase activity in "Sordum" plum was investigated to clarify the cause of hydrolysis of sucrose in the fruit during storage at high temperature (30°C). (1) Invertase activity in the fruit was high, but sucrose synthase activity was remarkably low. (2) Optimum temperature of invertase activity was 65-70°C. The enzyme was remarkably stable under 60°C for 15 min and became unstable above 60°C. Optimum pH of the enzyme activity was pH 5 and pH 9-11, and the activity at the former was remarkably high as compared with that at the latter. Km value of the enzyme was 2.56×10^-2M. (3) Invertase activity in the fruit increasedduring maturation and reached to the highest at around commercial ripeness, and after that de-creased. Invertase activity during storage at 3, 20 and 30°C decreased rapidly at the beginning of storage period, and at 3°C the decrease ratio was higher than those at other temperatures. The activities during storage after that did not change at 3°C and showed similar values at 20 and 30°C. Changes of the activities at 20°C were not consistent and those at 30°C increased at the latter stage of storage. The activities in fruits transferred from 3°C to 20°C decreased after the increase. The activities in fruits transferred from 20°C to 30°C increased and those from 30°C to 20°C decreased rapidly. (4) Sucrose content in the fruit during maturation increased remarkably after commercial ripeness, but glucose and fructose contents did not change. A little differences in sugar composition were observed in fruits during storage at 3 and 20°C. Whereas at 30°C the decrease in sucrose and the increase in glucose and fructose were observed with time of storage period. These changes became notable in the latter stage of storage and occurred in fruit transferred from 20°C to 30°C, too. (5) From these results, it is assumed that sucrose in "Sordum" fruit during storage at 30°C was hydrolyzed by inner invertase existed in the fruit and the hydrolytic change was strongly affected by storage temperature.

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A simple method for determination of ergosterol content in fruiting bodies of Basidiomycetes by gas-liquid chromatography (GC) was achieved by using n-octatriacontane as an internal standard. The same sample solutions were used for GC analysis of fatty acid composition. The fatty acids common to all 44 species of Basidiomycetes were found to be C_18:2, C_18:1, C_16:0 and C_18:0 acids, whereas L. chrysorrheus contained 6-oxooctadecanoic acid as main acid exceptionally. Ergosterol was contained in all samples analyzed, and its content ranged from 19 to 780mg per 100g of dry matter. The lowest content was observed in A. auriculrajudae and the highest content was in G. frondosa.

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In order to improve micro analysis of sulfur dioxide in various foods by modified RANKINE colorimetric method, absorbent and conditions for measurement were examined. Triethanolamine was preferable as the absorbent for the stability of sulfur dioxide for longer period. Forty % phosphoric acid containing 2, 4-dinitrophenylhydrazine was placed between absorbent and cooling condenser to eliminate alcohols and aldehydes because of interference in the coloring. Interference of other volatile surlfur compounds on the proposed method was less than the modified RANKINE method. Conditions for bubbling reaction were determined as follows: reaction temp., 70°C, bubbling gas and the rate, N2-800ml/min., acid, 40ml of 20% phosphoric acid. By the proposed method, high values of sulfur dioxide were obtained from foods added sulfur dioxide and low blank values also be obtainable from foods which was not added sulfur dioxide (containing other volatile sulfur compound).

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Texture and mouthfeel of textured Kamaboko like crab foot meat(Kani-like Kamaboko) were investigated by the biting test and the multi-point mensuration method using the Tensipresser. The special parameters obtained from Tensipresser bite profile curves of six commercial Kani-like Kamabokos were analysed, and compared with the result of sensory test related to the distinctive collapse mouthfeel of Kani-like Kamaboko. Parameters of cohesiveness(biting ratio 0.50, crosswise bite, a), αcoh(0.4-0.8) (slope of cohesiveness vs biting ratio fnom 0.4 to 0.8, c) and a×c measured by using a knife plunger were highly correlated to the ranking of the collapse mouthfeel by the sensory test. Parameters of HY(0.95) (hardness at apparent yield point in 0.95 biting ratio, crosswise bite), AI(0.95) (mechanical work load of the plunger in the first bite, 0.95 biting ratio, crosswise bite), F.I.(0.95) (fracturability index in 0.95 biting ratio, crosswise and lengthwise bite) and αAI(0.2-0.8) (slope of AI(0.95) mechanical work load of the plunger, biting ratio from 0.2 to 0.8) measured using by a plate type plunger were also highly correlated to the collapse mouthfeel by sensory test. Prominent textural difference between crosswise and lengthwise is the distigushing trait of Kani-like Kamaboko which would be derived from the process of preparation.

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