Changes in proximate components, antioxidative activity, sugar and lipid components of commercially available barley-koji miso during the storage of three months at -10, 4, 20 and 37°C were investigated. The results obtained were as follows: (1) When the storage temperatures kept below 20°C, the proximate components showed a little changes. When the storage temperature was 37°C, the amounts of direct reducing sugar and formol nitrogen decreased gradually, and especially, pH value was remarkably lowered with prolonging storage period. The coloring degree increased markedly with raising storage temperature and with prolonging storage period. (2) Antioxidative activity of barley-koji miso in the high temperature storage was stronger than that in the low temperature storage. (3) The major component of total sugar fraction and free sugar fraction was glucose, and the minor components of those were fructose, galactose, arabinose and xylose. Change in the content of free sugar in barley-koji miso during storage period was slight. However, it was inclined that glucose decreased and fructose increased with prolonging storage period and with raising storage temperature. (4) Total lipid content of barley-koji miso was 3.6%, and this value was unchangeable during the storage period. Triacylglycerol decreased, whereas fatty acid ethyl ester increased with prolonging storage period and with raising storage temperature. Free fatty acid decreased with prolonging storage period and with raising storage temperature. These results suggest that the lipase influenced the changes in lipid components and their fatty acid compositions under the various storage conditions.

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Eight species of lactic acid bacteria had been isolated from "Sunki" by Ohki NAKAYAMA²⁾. In order to determine the most effective species of lactic adid bacteria for sunki-pickles, the most effective species of lactic acid bacteria for sunki-pickles, the author tried to prepare sunki-pickles by using each single species of different lactic acid bacteria as a starter. The following results were obtained by chemical analyses and sensory test of the experimental products: (1) The pickles prepared by single species of lactic acid bacteria as starters are all rich in the crude protein content. (2) The pickles prepared by B. coagulans as a starter showed the largest values both in the total amount of tasty amino acids, i.e. aspartic acid and glutamic acid, and in sensory test compared with other pickles. (3) The highest and the lowest lactic acid contents in pickling juice were observed in the preparations by L. buchneri and S. faecalis, respectively.

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Wine-making was conducted using immobilized Saccharomyces cerevisiae OC-2 entrapped in calcium alginate, κ-carrageenan, agar and pectic acid gels. Calcium alginate gels were the best for the immobilization of yeast cells because of; (1) high yield of alcohol, (2) ease of preparation of gels, and (3) relatively small leakage of yeast cells from the gel during fermentation. Using the immobilized yeasts in a batch fermentation system, white table wine was produced from Koshu grape must. The levels of alcohol production and sugar consumption by immobilized yeast cells were fairly similar to the one achieved by free yeast cells (i.e. the usual method for making wine). The contents of total phenol, total nitrogen and ash and amino acid composition were somewhat different from each other, but there was no appreciable difference in the principal components.

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A fused silica capillary column gas chromatograph- mass spectrometer equiped with pyrolyser was used for the discrimination of natural food thickeners. Gum guar, Tamarind, Locust bean gum and Pullulan (Group A), and Gum karaya, Quince seed, Gum gahtty and Sodium alginate (Group B) are used as natural food thickeners. Group A has hydroxyl group and group B has hydroxyl group and carboxyl group and their salt. We examined the reproducibilities of pyrolysis products of Gum guar. The mean relative standard deviation was 7.06% which was enough to the discrimination of natural food thickeners. When each pyrogram was examined each other, 5-hydroxymethyl-2-furfural was only detected from group A and not from group B. Group A and B were able to discriminate in which searched this pyrolysis product. The group B were able to discriminate in which identified each main pyrolysis products such as acetic acid (Gum karaya), furfural (Sodium alginate) and methanol (Quince seed and Gum gahtty). But group A were impossible to discriminate because their pyrogram has similar pattern. Moleculer ion peak of common pyrolysis products such as furfural, acetic acid, methylglyoxal, acetol, 2-hydroxy-3-oxobutanal, 3-methyl-2-hydroxy-cyclopentenon and 5-hydroxymethyl-2-furfural are used as mass chromatography. Therefore group A were able to discriminate in which used pyrogram.

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Invertase activity, sulfur concentration and sugar composition in dried astringent persimmon fruit ("Hoshigaki") were estimated during sun- drying after sulfur fumigation. (1) SO₂ concentration of fruits decreased markedly to 30% of the initial level at the 6th day of drying. (2) Water-soluble protein content and total invertase activity in acetone powder of fruits decreased remarkably by sulfur fumigation, and after that, they decreased with the progress of drying. But the former increased after the 12th day of drying. The specific activity of invertase (invertase activity per μg protein) did not change by sulfur fumigation but gradually decreased during the drying process. (3) Sucrose in fruits was hydrolyzed immediately after sulfur fumigation and was not detected after 24th day of drying. Dried fruit flesh and the white powder formed on the surface of dried fruit contained only glucose and fructose in the ratio of 51 to 49 and 79 to 21, respectively.

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For the final process to produce sweetened Adzuki Ann (Bean Jam), the cooked beans, after washing with water, is subjected to kneading with sugar and water during heating, which is a very important procedure for the quality of products. In the previous paper, the modified method for preparation of the cooked beans to improve the quality, as well as to increase the yield, was reported. And for the modified cooking, Adzuki bean was heated in boiling water by using a metal basket as the container of beans during heating, which was designed to have a definite capacity as much as 2.22 times the volume of the raw beans used so as to limit the expanding volume of swelled beans up to the capacity of the basket. In this paper, using the cooked beans, being boiled for 90min. by the modified method, a result of further studies on the kneading conditions was described. In comparison with the usual method in the same conditions, it was found that the modified one gave more sticky Ann with increased amount of free starch during kneading, showing inferior qualities estimated for the properties of hardness, stickiness, apparent volume, water holding capacity and water activity (Aw). To improve the qualities of the final product by decreasing the free starch content, a new method of kneading was developed with regard to the control of the vigorousness and the length of time of kneading. The results obtained were as follows: (1) Slowing down of the stirring speed of a kneader to about 1/2 of those currently in use was the most effective condition, giving the product as of better or same quality as the usual one. (2) Decreasing the length of kneading time was not applicable, because water was liberated from the tissues of Ann during cold storage by retrogradation of gelatinized starch, though free starch content was decreased. In this case, it was assumed that the amount of sugar dispersed into the cell granules was not enough to prevent retrogradation of starch, for which the length of kneading time was responsible.

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Quantitative and qualitative changes of pectin during development of Satsuma mandarin fruits (Citrus unshiu Marc.) was investigated. Alcohol insoluble solid (AIS) content decreased in flavedo and albedo parts and increased in membrane part during fruit development as fresh weight basis. Hydrochloric acid soluble pectin (HSP) was major fraction among four soluble pectin fractions in AIS during fruit development. In flavedo, albedo and juice sac parts HSP has increased, but there was little increase in membrane part from the middle of August to the early of December. Anhydrogalacturonic acid content in pectin prepared from fruit components decreased in albedo part and increased in juice sac part. In fractioned acidic polysaccharide, arabinose was a major component among neutral sugars. Arabinose, galactose and glucose occupied about 80% in total neutral sugars. There were little changes in the compositional ratio of neutral sugars during fruit development. Little changes in degree of esterification and average of molecular weight of pectin were observed during fruit development, but their properties differed among component parts.

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Effects of dietary soybean oil, coconut oil, lard and beef tallow on the composition and structure of triacylglycerol (TG) of abdominal adipose tissue and skin lipids of laying hens were studied. Fatty acid compositions of adipose tissue and skin TG from each dietary group fairly well reflected the fatty acid pattern of respective fats fed to hens. The lipids from soybean oil, lard and beef tallow feeding groups comprised the TG of C₅₀, C₅₂ and C₅₄ as the major TG components, and that from coconut oil feeding group contained large quantity of medium chain length TG of C₃₆-C₄₈ in addition to the C₅₀-C₅₄. Species composition of TG was determined by argentation thin-layer chromatography. The lipids from soybean oil group contained more amounts of TG of U₃ and SU₂ than that from the other dietary groups, and the lipids from coconut oil group were abundant in TG of S₃ and S₂U. Generally, C_16:0 and C_18:0 were preferentially esterified at position 1, and C_18:2 was predominated in position 2 of TG from adipose tissue and skin of hens. Short chain fatty acids contained in tissue lipids from coconut oil group were largely distributed in position 3. The most abundant TG in lipids from soybean oil, lard and beef tallow groups was sn-UUU, followed by sn-SUU and sn-UUS, and major components TG of lipid from coconut oil group were sn-SSS, snSUS and sn-USS both in adipose tissue and in skin lipids of laying hens. Conclusively, it was recognized that the influence of dietary fats on the composition and structure of TG appeared more markedly in the adipose tissue than in skin lipids of laying hens.

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A new method for measurement of diffusion, permeation and sorption coefficients of volatile compounds in polyethylene (PE) film was established. The activation energies for the diffusion in middle density PE (MDPE) of n-octane, ethyl caproate, n-octanal and noctanol were 14.6, 10.5, 15.0 and 19.2kcal/mol, respectively. Although the molecular volumes of penetrants were the almost same value, it was indicated that the hole volumes in the PE required for the penetrants to diffuse or jump were quite different. The enthalpy changes in sorption from vapor phase were -9.1, -8.2, -2.7 and -10.7kcal/mol, respectively, that is, all the sorption were exothermic process. The decrease in enthalpy was associated with the increase in boiling points of penetrants and the increase in affinities for PE.

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