Polyphenol compounds in six plum varieties were studied to elucidate the relationship between the contents and enzymatic browning of the plums by crushing. The total contents of polyphenols were 167 (Santa Rosa) to 250 (Sordum) mg%. The ratio of flavanol tannin and chlorogenic acid to the total polyphenol was almost same, 86 to 99% of the polyphenols were consisted with these compounds. The degrees of the enzymatic browning of the plums by crushing were as follows; Methley>Sordum>Ooishi Wase>Beauty>White Plum>Santa Rosa, on the other hand, the color of the juice of "Santa Rosa" did not change. Optimum pH and temperature of the enzymatic browning were pH 4.5 to 5.0 and 35°C. The polyphenol extracted from "Methley" plum was not oxidized for 50 days at 30°C by the addition of potassium metabisulfite.

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"Ooishi Wase" plums were stored for 30 days at 3°C, for 8 days at 20°C, and at 20°C following 3°C. The hardness and weight of plums during storage at 20°C readily decreased, and red pigments in the peel of plums also readily developed. The plums deteriorated after 3 to 5 days. Some changes in chemical compositions in juices from the plums were occurred when stored at 20°C. The amounts of free-amino nitrogen and sucrose increased, and those of titratable acid, glucose, and fructose decreased. Hydrochrolic acid-soluble pectin at harvest season was principal pectin in the plums, but it decreased readily contrary to the increase of water-soluble pectin during storage at 20°C. At 3°C little changes were observed except softening and weight decrease of the plums. Changes in the qualities of the plums stored at 20°C following 3°C storage were simillar to those of the plums stored at 20°C.Free-amino acids in the juices showed tendency to increase during storage. Especially, the amounts of alanine after storage for 8 days at 20°C increased 7 to 8 times at harvest season. Respiration rate of the plums increased with increasing the storage temperature.

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The effect of sodium perchlorate on the spectral and polarographic behavior of malvidin-3, 5-diglucoside chloride was studied in the acidic solutions. (1) Addition of sodium perchlorate to malvidin-3, 5-diglucoside solution (pH 2.3) caused the increase of absorbance at 520 and 275nm.(2) Addition of sodium perchlorate to malvidin-3, 5-diglucoside in citric acid-disodium hydrogen phosphate buffer (pH 4.0) caused the increase of the first wave (-0.46 V vs. SCE) and the decrease of the second (-0.92 V vs. SCE) accompanying the positive shift of the halfwave potentials. (3) The spectral and polarographic behavior with the increase of concentration of sodium perchlorate corresponded to those with the decrease of pH. (4) The flavylium salt (colored form)-carbinol base (colorless form) equilibrium in malvidin-3, 5-diglucoside solution shifted toward the former form when sodium perchlorate was added. (5) These evidences suggested that the hyperchromic effect (enrichment of absorbance at 520nm) of sodium perchlorate on the acidic anthocyanin solutions resulted from the conversion of colorless form into colored form (flavyliums alt).

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The study was done to determine the effect of irradiation on the shelf life and quality of a fish meat jelly product named as Fried-Kamaboko which is sometimes called as Satsumaage. Fresh samples were packed and sealed in cellophane coated polyvinylchloride bag with nitrogen gas, and irradiated at 0, 300 and 500 krad followed by storage at 10°C. The results showed that irradiation of 300 krad extended the shelf life of Fried-Kamboko to be 20 days, in contrast to unirradiated samples which were kept only 3 to 6 days at 10°C. The species of main microorganisms which grew in unirradiated samples were Micrtococcus, Moraxella-Acinetobacter, lactic acid bacteria, yeasts and molds. Irradiation of Fried-Kamboko at 300 krad reduced the aforementioned flora to the yeasts. The most radio-resistant microorganisms of Fried-Kamaboko was brownish black Fungi identified as Spicaria, and its D10 value was obtained to be 130 krad. No remarkable difference was observed between the irradiated Fried-Kamaboko and unirradiated ones with respect to the organoleptic evaluation. But off-odor was slightly induced with the dose of 500 krad irradiation.

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Solubilization technique of oily substances into micellar solution of protein and carbohydrate was applied to encapsulation of oil-soluble pigment, paprika oleoresine or β-carotene. The solubilizates of the pigment in oil into the aqueous solution of 60%(w/w) corn syrup solids, 1% (w/w) polypeptone as nitrogen were solidified at 60°C under the vacum drying. The granules obtained by crushing and sieving the dried material showed a considerably high encapsulation ratio of pigment. Discoloration of the granulated pigment during 20 days storage at 60°C or under the irradiation by a fluorescent lamp was scarcely occurred when the granules contained abodt 12% oil containing paprika or β-carotene. Dispersibility into water of the oil-soluble pigment was also improved through the encapsulation into the protein-carbohydrate matrix.

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"Sordum" plums were stored at 3°C for 30 days, (at 20°C) for 15 days, and at 20°C after 3°C storage, respectively. During storage at 20°C, the hardness and the weight of them rapidly decreased, whereas red pigments in the peel and pulp steeply developed. The increase of the amounts of free-amino nitrogen, total surgars and polyphenols was also observed in the juice. The plums detriorated in 7 to 10 days. Hydrochloric acid-soluble pectin which is a major component of pectin in plums at harvest decreased rapidly in proportion to the increase of watersoluble pectin during storage at 20°C. These changes were little observed during storage at 3°C except softening and weight loss. Changes of the qualities of the plums stored at 20°C after 3°C were remarkable. Free-amino acids in the juice had a tendency to increase at the beginning and the middle of the storage and to decrease at the end. Plorine and alanine readily increased at 20°C, and alanine content became 8 times higher than the value at harvest.

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The amonts of free sugar, free sugar alcohols and organic acids inthe eight grades (Hanadonko, Jyodonko, Namidonko, Kotsubudonko, Jyokoshin, Namikoshin, Chayori and Kuroko) of dried Shiitake mushroom were determined by gas-liquid chromatography. The amounts of D-arabitol, D-mannitol and rehalose were 1.2-7.7%, 2.2-6.2% and 3.7-9.4% respectively. Donko type was especially rich in trehalose and D-arabitol, and Koshill type was rich in D-mannitol. Organic acid contents were found in the range of 1.1-1.5% in samples and ten kinds of organic acids were identified. Malic, Fumaric, Pyroglutamic, and Citric Acids were found to be major of them. Donko type was especially rich in pyroglutamic and citric acid, whereas Koshin type was rich in fumaric acid.

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Three kinds of coffee beans (Colombia, Santos, and Madagascar) roasted to four roasting stages respectively, were brewed by the cup-test procedure, and pH values were measured immediatly. The pH value of any kind of coffee fell to minimum at light roast, but began to rise at a subsequent roasting stage. The degree of this falling pH increased by order of Madagascar, Santos, and Colombia. Along the lowering temperature from 70°C to 26°C, the pH fell within ranges of 0.04-0.26. Santos indicated relatively susceptible effect of temperature on the otherhand, Colombia indicated moderate effect, and Madagascar, indicated little effect. It was suggested that these results correlated to organoleptic quality of coffee used in this experiment.

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The rate of water absorption of U.S. soybeans has been measured at temperatures ranging from 5°C to 70°C, and initial moisture levels ranging from 4.2 to 12.7%. The rate of water absorption was markedly influenced by the soaking temperature; apparent activation energy for the water absorption was calculated to be 9400cal. mole^-1. Apparent specific surface area of soybeans increased linearly with an increase in water content of beans. Rate coefficient of water absorption, on the contrary, decreased with an increase in water content of the beans. No fundamental difference was observed in the rate of water absorption of sound and abrased soybeans.

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