Two grams of "Shiratama-ko", commercially available flour which was prepared from polished waxy rice grains, almost freed from water soluble substances and chiefly composed of waxy rice starch, was mixed with 1.6ml of an aqueous solution or water suspension of some vitamins, amino acids or their derivatives, and then heated. The resultant pastes were stored at 2°C. The hardness of the paste was followed by measuring the gel strength by means of a curd meter. It was found that the addition of less than 2g of the following compounds per 100g of Shiratama-ko decreased the gel strength of the paste; nicotinic acid, nicotinamide, paminobenzoic acid, tryptophan, phenylalanine and some derivatives of nicotinic acid, benzoic acid and tryptophan. The addition of 1.6g nicotinamide per 100g of Shiratama-ko decreased the gel strength of the paste stored at temperatures between 8 and 12°C, and increased beetween-10 and -13°C, on the contrary.

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Mature-green banana fruit was stored at temperatures of 20, 25, 30, 35 and 40°C. The initiation of ripening and subsequent ethylene evolution, pulp softening and sugar accumulation were accerelated with elevation of storoge temperature up to 35°C. But the degreening of peel was inhibited above 30°C and the evolution of volatile compounds was suppressed at 35°C and over. When mature-green banana fruit was stored at 40°C, it showed no ethylene evolution and nothing of ripening phenomenon and external ethylene treatment to the fruit did not induce ripening. The fruit which was once initiated ripening with ethylene treatment showed ethylene evolution and pulp softening during subsequent storage at 40°C, but sugar accumulation in the fruit was smaller than that of fruit ripened at 20°C and evolution of volatile compounds was prevented during the storage. When mature-green banaa fruit stored at 40°C for 1, 2, 3 and 5 days were transfered to 20°C and then treated with 500ppm ethylene for 24hr, the fruit stored at 40°C for 1, 2 and 3 days ripened, but for 5 days did not.

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Equilibrium of water-soluble protein petween water and flesh of Alaska-pollack was studied. It was difficult to determine the concentration of solute in flesh phase, so that experiments were carried out by determining the concentration of liquid phase (y) only, and the concentration in flesh phase (X) was calculated. Equilibrium equation was derived by assuming as follows. The flesh phase consisted of solution part and of flesh part, and the quantity of solute included in flesh phase was the sum of duantity included in both parts. The concentration of solution part (x) was equal to the concentration of outer phase y, and the contration of flesh part kyⁿ was equilibrated with the concentration of solution in flesh part. Following equation thus derived was agreed well with experimental results.
X=3.76×10^-4y+2.16×10^-5y^0.186
The concentration of water-soluble protein was determined applying the method of colloidal titration by using anionic high polymer electrolyte, PVSK solution (Pottasium polyvinyl sulfate) and TB (Toluidine blue) solution as an indicator at pH 1.6. The equivalent weight of watersoluble protein to PVSK was determined to be about 870.

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Extraction rates of water-soluble protein from flesh of Alaska-pollack and from a porous plate which had been immersed in protein solution were studied. Measurements of mass transfer rate from sliced fleshes were carried out on both cases which the directions of mass transfer were perpendicular to and parallel to the direction of fiber. Mass transfer rate from crushed fleshes and porous plate were also determined. The rate of mass transfer of which direction was parallel to the direction of fiber was greater than the other. Mechanisms of mass transfer were different for each direction. The transfer rates were the function of t/L^1.5 for the direction parallel to fiber, and t/LL² for the other. But both extraction curves drawn respectively as the function of t/L^1.5 and of 0.28t/LL² were coincidence with each other. The rate of extraction from crushed fieshes was explained approximately by equation which was derived by considering distribution of diffusivity with D/LL²=9.38×10^-5(1/sec.), y(=D/δ)=1.15 for plain sheet or with D/aa²=1.45×10^-4(1/sec.), y=1.15 for cylinder. On the other hand, the rate of extraction from a porous plate was well explained by the equation with kD (=ππ²D/LL²)=5.33×10^-5(1/sec.), y=1.15, and D/DNaCl=0.36 was obtained in porous plate.

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The previous work has shown that the formulation containing sugar fatty acid ester and potassium pyrophosphate gave good effect on peeling of Satsuma Mandarin segments. In the present work, application of the formulation to an industrial usage was studied with respect to the following points; (1) Durability of the peeling effect; (2) Stability of the formulation in HCl and NaOH solutions; (3) Influence of the formulation on muddiness in syrup, flavor and other quality of canned Satsuma Mandarin segments; (4) Content of the formulation residue in peeled segments; (5) Foaming power of the peeling solution; (6) Peeling effect at several plants. From the view point of the application, desirable results were obtained by the tests mentioned above. In addition, segmentation by machine was more effective for peeling of the segments than that by hand. Furthermore, peeling condition by Taru method was relatively mild as compared with that by Toyu, regardless of the presence of the formulation.

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For the purpose of quantitative identfication of vegetable proteins in animal protein products, SDS polyacrylmide gel electrophoretical patterns of various animal and vegetable proteins were compared. The identification of soybean protein was possible by this method, while wheat protein was impossible, because the major bands of wheat and animal proteins were recognized at the almost same position on the electrophoretical pattern.

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Urea polyacylamide gel electrophoresis was investigated for quantitative identification of soybean and wheat proteins in animal protein products. Samples were first treated with 10M urea and 2% mercaptoethanol for 3-24hr at room temperature and then applied on pH 3.5 polyacrylamide gel containing 8M urea. The majer protein bands of these proteins were distinguished each other on the electrophoretical patterns, so that it was possible to identify the soybean and wheat proteins at the same time in animal protein products like meat analogues.

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For the production of soaked rice of high level moisture which can be weighed and packed easily in a container, soaking method of superheatedsteam-treated rice was reported in a previous paper. In this paper, the soaking method of microwavetreated rice is presented for the same purposes. Whole raw rice (moisture content 14%) was soaked for 2 hours at 30°C, and then the soaked rice (moisture content 32%) was treated for 75sec with 240 wattes per 7g of soaked rice in a microwave even. Thus treated rice (moisture 31%) was soaked again at 30-90°C for a certain time. The hydrated rice up to 55-60% of moisture level were similar to the products of the previous paper in respect to the pasty characteristics.

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