We have investigatated the precipitation reaction of albumin, casein, gelatin and sericin solution in the presence of sodium polyphospate. The relation between the character of polyphosphates and the precipitation of protein aqueous solution were studied. When ultra-, or hexametaphosphate were added to albumin or gelatin at pH 3 to 7, the degree of turbidity and gel weight remarkably increased, and the peaks of turbidity appeared at acidic side. In case of casein or sericin solution the degree of turidity and gel weight were less than the case without polyphosphate at lower pH. Pyro-acid pyro-, and tripolyphosphate did not influence on the precipitation reaction for all proteins at various conditions. It was suggested that the precipitation reaction of protein aqueous solution were influenced by chelation value, part of high polymer and ring structure of polyphosphates. The correlation was observed between the average chain length in the meta or ultra region of polyphosphates and the degree of turbidity of each protein aqueous solution. However, the smaller chain length of polyphosphates had no relation to them.

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The densitometric protein patterns of the proteins in "Mugi-miso (barley-miso) were investigated by urea polyacrylamide gel electrophoresis. The proteins of soybean, rice and barley were identified by this method. Furthermore, "Mugi-miso" (barley-miso) made from soybean and barley could be discriminated from rice blended "Mugi-miso" (barley-miso). The height of barley protein band was nearly proportional to the barley content in "Mugi-miso" (barley-miso). Nine samples of the commercial "Mugi-miso" (barley-miso) were examined to detect their raw materials, and their mixing ratios. The ratio was 1 to 3 parts of barley to 1 part of soybean.

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"Konnyaku", a traditional food of Japan, is a moist and elastic gel made from the flour (glucomannan) of the devil's tongue, Amorphophallus konjac K. Koch. The organoleptic analysis of the texture characteristics of this food was carried out on 20 samples of different grades. Close relationships were found between "quality" and "toughness" score, as well as between "quality" and "hardness" score. These subjective reactions were related to 2 kinds of objective indexes: the breaking strength S (g) and the breaking deformation d (cm), both of which were obtained for the specimen of 3.0cm thick by the penetrating test using Okada's jelly-strength tester fitted with a plunger of diameter 0.80 cm. The logarithm of S varied directly with the "hardness" score, and that of S·d varied directly with the "toughness" score. The d value varied directly with the "quality" score. The desirable ranges for this food were estimated to be 500-700g for 3 and 700-1, 000g·cm for S·d.

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The sol-marking property and the konnyaku-forming ability of konjac flour (gluco-mannan) were investigated on 9 samples from 3 varieties, native, shina and haruna-kuro, in connection with their grades. The viscosity of the 1% sol, ηc=1% measured by a Brookfield-type viscometer closely related to the grade of the flour except 2 samples from shina, which seemed to be a peculiar variety producing a fragile gel in spite of its ability to make a highly viscous sol. The breaking strength, S (g) and the breaking deformation, d (cm) of the konnyaku-gel, both of which were obtained by the penetrating-test using Okada's jelly-strength tester, were also examined as measures of the flour grade. S was related to the concentration C by the following equation; S=kCⁿ, where the parameter k was almost the constant value ca. 100g without regard to the kinds or grades of the flour, whereas n varied 1.3 to 1.8 with the flour grade. On the other hand, d was little influenced by the concentration and the values seemed to be intrinsic for each kind of the flour. ηc=1% and n and d for the 3% gel were recommended as the objective measures for evaluating the qualities of konjac flour.

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Changes of physical property and chemical composition of plums during maturation were investigated using "Ooishi Wase" and "Sordum" variety which were harvested in Yamanashi Prefecture at the period of 15-20 days before full ripeness. The following results were obtained: (1) The increase of weight and the decrease of hardness were observed during maturation. (2) Developement of Red pigments over the peel of "Ooishi Wase" and in the pulp of "Sordum" were observed at the end of the harvest period. (3) The contents of titratable acid in "Ooishi Wase" decreased during maturation, and that of total and reducing sugars in "Sordum" plum increased. (4) Hydrochloric acid-soluble pectin was the main part to total pectin at the beginning of the harvest period, and decreased during maturation. Water-soluble pectin in "Ooishi Wase" increased at the end of the harvest period, on the other hand, that in "Sordum" plum did not change. (5) Glucose, fructose, sucrose and the trace amounts of xylose were detected in the juices, and their contents changed during maturation. The amount of sucrose in "Sordum" increased, especially.

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