In order to find the factors concerning the accumulation of nitrate in tomato fruit, the influences of phosphate, potassium, calcium and magnesium fertilizers were investigated. Low levels of these fertilizers and three levels of phosphate and potassium in factorial combination were applied to Fire Ball variety in sand culture.
When tomato plants were grown with the low level of potassium, the nitrate content in the fruit was very low, and potassium contents in the fruit and leaves were of low level.
The influence of phosphate on the nitrate content was not clear. With lowering of each of calcium and magnesium levels, no significant influence was observed on the nitrate accumulation in the tomato fruit.
The nitrate content in the tomato fruit changed during ripening, and according to various fertilizer tests four types of change were observed from the breaker through the red ripe stages, remarkable decrease, slight decrease, no change, and slight increase.

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A gas chromatographic method was studied for the analysis of acidulants in soft drinks. Sample solution, after decarbonation if necessary, was treated with ion exchange resins to isolate the organic acids. The eluted acid solution with 2N ammonia was evaporated to dry and converted to 1-butyl ester by refluxing in 1-butanol, HCl and anhydrous sodium sulfate. Using dual hydrogen flame ionization detector and stainless steel column (2m×3mm i.d.) of 5% DEGS and 1% H₃PO₄ on Chromosorb W on a YANAGIMOTO GCG 550 FT, nitrogen flow rate of 25 ml/min and temperature programming between 80 and 200°C at a rate of 6°C/min were selected as optimum conditions for the separation and determination of acid esters.
The average recovery of butyl ester of fumarate, malate, tartarate and citrate were 94, 92, 78 and 102% respectively.
Eight commercial samples of carbonated soft drink and three of soft drink powder were analyzed by this method. For carbonated soft drink, 0.07-0.14% of citric acid was found in six brands and 0.09% of tartaric acid in one brand and 0.01% of malic acid and 0.05% of citric acid were found in another. For soft drink powder, 2.57% of citric acid in one brand and 0.49% of fumaric acid in one brand and 0.05% of fumalic acid, 0.07% of malic acid and 1.09% of citric acid were found in another.

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Albumin and globulin in rice endosperm were investigated, on their heterogeneity and the difference in subunit composition among three rice samples, stored, heated and control. Albumins and globulins in rice endosperm were both highly heterogeneous; albumins gave eleven bands and globulins gave eight bands by the starch-gel electrophoresis at pH3.1, albumins gave fifteen and globulins gave eight bands by the starch-gel electrophoresis at pH8.9, albumins gave nine and globulins gave six bands by the disk electrophoresis, and albumins gave four and globulins gave three peaks by the gel-permeation chromatography.
Three albumins extracted from stored, heated, and fresh rice gave bands and peaks at the same positions, they must have very similar compositions. Three globulins gave bands and peaks also at the same positions.
But three albumins as well as three globulins were not completely of the same compositions. Intensity of bands by electrophoresis was appreciably different among the three, and the height of peaks or area of fractions by gel-permeation chromatography was also different.
Albumin and globulin content in stored and heated rice endosperm were smaller than that of the control. A part of albumin or globulin whose solubility had widely changed during storage or heating should not be extracted as albumin nor globulin.

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Studies were made to investigate whether miso and miso-koji (a solid culture of industrial koji-mold strain on rice)in Japan contained aflatoxins or not.1080f the commercial miso, 33 of home made miso and 28 of miso-koji from almost all the prefectures of Japan were tested for their aflatoxin contamination and toxicity by the methods of thin-layer chromatography, liquid chromatography, UV absorption and chicken embryo bioassay (yolk sac test). As the results of aflatoxin contamination test, no aflatoxin was detected from any of them. But on the thin-layer chromatograms, 3 commercial misos, one home made miso and 2 miso-kojis showed aflatoxinlike fluorescent substances. The extracts of these aflatoxin-like substances were examjned by yolk sac test for their toxicity to chicken embryo. The results however were all negative.

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The precipitation of tannin with soluble polyvinylpyrrolidone (PVPs, MW 40, 000 and 360, 000) was scarcely affected by pH in acid solution but not developed in alkaline solution. The production of precipitate was prevented by the presence of borate ion, Na₂SO₄, and ethanol, and decreased with the rise of temperature. The ratio of removal tannin to original one changed under the control of the concentration ratio of tannin to PVPs and when PVPs was 2.9 times as much as tannic acid, the precipitate became greatly soluble. Among several polyphenolics, only high molecular tannin was precipitated. These results show that the tannin precipitation activity of PVPs is resemble to the case of methyl cellulose.

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In previous reports, it has been shown that all soluble tannin removal agents, methyl cellulose, polyethers, and soluble polyvinyl pyrrolidone were able to precipitate high molecular tannin but not low molecular polyphenolics. But, inversely, insoluble polyvinylpyrrolidone (PVPi, Polyclar AT) largely adsorbs low molecular polyphenolics, such as catechins, anthocyanins, naringin etc., and the larger the molecular weight of tannin, the smaller the adsorption. Adsorption of catechin and tannic acid is scarcely affected by pH, and that of anthocyanin decreases under pH of 5. The temperature of maximum adsorption of catechin and anthocyanin is 50° and 30° respectively. But tannic acid is greatly adsorbed over 50°. The effects of the coexistence of sucrose, Na₂SO₄, and ethanol are also different according to the size of molecule of polyphenolics. When juices of strawberry and grape were treated with PVPi, juices were practically decolourized as a result of the removal of anthocyanin. When the extracts of grape, loquat, and tea were treated, most of tannin and little of chlorogenic acid remaind. It is, therefore, concluded that PVPi would be utilized for removal of low molecular polyphenolics and stabilization of beverages.

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The content of As in tea plant was determined by neutron activation analysis.
1) The content of As could not be determined by non-destructive activation analysis, using Ge (Li) γ-ray spectrometer, because γ-ray peak of 76As on the spectrogram is masked by γ-ray peak of 82Br which exists in tea and has very similar γ-ray spectrum.
2) After destruction of tea plant with acid, Br in tea plant was distilled off from the acid destructed solution and γ-ray peak of 76As was evidenced on γ-ray spectrogram of the acid destructed solution.
From the height of γ-ray peak of 76As the contents of more than 0.2μg of As in tea plant were determined quantatively.
3) By using the Gutzeit method, As in tea plant was separated from other elements and two characteristic γ-ray peak of 76As were figured on the γ-ray spectrogram.
From this spectrograms, more 0.05μg of As in tea plant were detected quantitatively.

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To elucidate the mechanism of the increase of reduced viscosity of soybean protein in alcohol solution, the behavior of the protein was studied using viscosity, ultracentrifugation, and turbidity. Reduced viscosity of soybean globulins was determined between 0.1 to 1.5% protein concentration in the presence of varying concentration of alcohols in 0.076 M tris-citrate buffer. Reduced viscosity as a function of alcohol concentration was found to be maximal at 30% propyl, 40% ethyl, and 50% methyl alcohol, and thus was a function of the size of the alkyl group. Ultracentrifugal analysis showed that the main component of soybean protein was polymerized in alcohol solution.
Therefore, the increase of viscosity of soybean protein in alcohol solution is a result of pylymerization of the protein molecule rather than unfolding.
The increase of viscosity of the protein in alcohol solution was accelerated by low concentration of 2-mercaptoethanol, a reducing agent of disulfide bonds. After 24 hours in the presence of 2-mercaptoethanol, viscosity and turbidity measurements showed similar increases. Therefore, it was clear that 2-mercaptoethanol accelerated the polymerization of protein in alcohol solution.

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