The green tea brew was fractionated into five groups by column-chromatography using Sephadex G-75 eluted by distilled water. The fraction 1 contained compounds with high molecule weights such as pectin and watersoluble protein. The fraction 2 and 3 contained caffeine, amino acids and sugars. The fraction 3 contained flavonols and some phenolic substances except catechins. The fraction 4 and 5 contained simple catechins and galloyled catechins, respectively.
The intensities of bitterness, astringency, brothy taste and sweetness of these five fractions and green tea brews were estimated by sensory evaluation. Seventy or seventy five percentage of bitterness and astringency were caused by the fraction 4 and 5, and about twenty percentage of these taste were caused by the fraction 3. About seventy percentage of brothy taste and sweetness were caused by the fraction 2 and 3.
Bitterness and astringency of fraction 4 and 5 and green tea brew almost eliminated by removal of polyphenic compounds using Polyclar AT. Brothy taste and sweetness of green tea brew decreased to about thirty percentage and fifty or seventy five percentage of original intensities by removal of amino acids using ion-exchange resin.
It is suggested that bitterness and astringency of green tea brew are almost responsible to catechins and other phenolic compounds, and brothy taste is mainly responsible to amino acids, and sweetness is considerably responsible to sugars.

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The effects of heated air and infrared radiation on the rising of the surface temperature of Satsuma orange (Citrus unshiu Marc.) were formulated mathematically. The heating and cooling curves were analyzed by using the formulae. The results obtained recommend a method in which the specimen is initially heated by infrared irradiation followed by blowing forced heated air so as to obtain perfect drying. A simple method of design calculation using a numerical table was given.

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Vienna sausages get spoiled by slime production or putrefaction due to the propagation of microorganisms. when stored only for 3 to 5 days at 10°C. The radiation pasteurization of vienna sausages has mainly been studied with gamma irradiation. The slime of sausages is believed to be microorganisms themselves growing on the surface of sausages. Pasteurization of the surface of vienna sausages with electron irradiation was thus investigated. The results obtained are as follows:
The vienna sausages irradiated with a dose of 0.8-1.0 Mrad by 0.5MeV electrons could be stored without slime production or putrefaction for more than a week at 11°C. The effect of pasteurization increased with energy and dose of electrons. However, the changes in the organoleptic qualities of vienna sausages were detected when irradiated with a dose of over 0.7 Mrad by 2.0MeV electrons. Consequently, the irradiation with a dose of 1.0 Mrad by 1.0MeV electrons was effectual in lengthening their shelf-life without deterioration of the organoleptic qualities.

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The pH-drops of sugar liquors treated with reverse system of ion-exchange resin was studied. The results obtained were as follows:
1. The effluents from the ion-exchange resin of reverse system (IRA-900-IRA-75) of sugar liquors containing reducing sugars, such as glucose solution, fine liquor or affined sugar solution, indicated lower pH value. However, in the case of sucrose solution such a tendency was not observed.
2. It became apparent that this pH-drops of the effluents were caused by organic acids, including lactic acid, glycolic acid, etc., which were produced by the interaction of reducing sugars with strong basic anion-exchange resin.
3. It was recognized that the presence of sucrose and/or inorganic salt in the sugar liquors containing reducing sugar caused increase of the amounts of leaked organic acids.
4. The serious problem, that is pH-drop of sugar liquor treated with the reverse system, was improved satisfactorily by the retreatment of the sugar liquor with an anion-exchange resin such as IRA-93 (OH) or IRA-900 (CO₃).

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In this paper were investigated differences in amino acids in endosperm of rice samples dried by two different processes. Total amino acid content in a heat-dried rice sample was almost three times that in a usual sun-dried rice sample. A pattern of the individual amino acid increment obtained in this case was significantly correlative to that observed when the sun-dried rice sample was artificially autolyzed in the presence of water. It was tentatively concluded that some enzymatic reactions positively proceeded during drying of raw rice under a wet state and was responsible for giving a specific pattern of free amino acids to the heat-dried rice.

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Effects of ultra violet rays irradiation combined with vaccum packaging on the storage of pickled radish were examined at 30°C to obtain the following results.
1) Deterioration took place after 10 and 35 days storage in the cases of ordinary packaging and vaccum packaging, respectivery.
2) Preservation period of the specimen vaccumpackaged after irradiation was extended slightuy by olganoleptic test as compared with that of vaccum packaging, whereas chemical constituents were almost same in both cases.
3) Degree of deterioration was paralleled to the decrease of sorbic acid during storage.

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Fried soybean curd (Abura-age) is one of the favorite foods among Japanese. In a Previous paper, the authors observed the presence of a toxic dimer of triglyceride in oils which were used for frying of some foods, especially in rapeseed oil used for Abura-age.
In order to judge the quality of frying oil used for Abura-age, some more samples were analyzed. The used soybean oils were collected from Aburaage manufactures. Analytical data indicated that most of oils were deteriorated and two of them contained fairly high amounts of toxic dimer of triglyceride (2.4 and 1.1%, respectively).

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