The initial protein was prepared from the defatted meal of unmatured soybean seed with urea by the column chromatography on DEAE-Sephadex A-50 and Sephadex G-150. The prepared protein showed a single peak (S₂₀, W=apporoximately 1.2) on the ultracentrifugal pattern and a single band on the starch gel electrophoretical pattern with urea. Also the molecular weight was estimated as 23, 000 from gel filtration with 8M urea on Sepharose 6B.
Little difference was found between the initial protein and 7S globulin from the matured seeds about amino acid composition, N-terminal amino acid composition and isoelectric point (apporoximately 5.10) by the method of isoelectrofocusing.

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Investigations were carried out on the use of Cobalt-60 gamma irradiation for Indian meal moth, Plodia interpunctella, which is one of the main cereal insects in Japan.
Eggs, larvae and pupae were irradiated at each stage and held until emergence was complete. Then LD₃₉ and LD₅₀ values were determined from curves on the probit scale.
The LD₉₉ values required to prevent hatching of 0 day old eggs and 2 days old eggs were 2.75Krad and 35Krad, and the LD₅₀ values were 1.5Krad and 22Krad, respectively.
The LD₃₉ and LD₅₀ values required to prevent adult emergence were 1.2Krad and 0.6Krad for 0 day old eggs, 5.6Krad and 3.3Krad for 2 days old eggs, 8.3Krad and 4.5Krad for first instar (7-10 days old) of larvae, 9.2Krad and 5.3Krad for last instar (30-33 days old) of larvae, and 33.5Krad and 16Krad for pupae.
The emergence of adult can be prevented by 40Krad of gamma irradiation applied to naked eggs, larvae and pupae.
All the emerged adults from each stage when irradiated with 20Krad, lost their fertility.

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The dormancy period of onion, Cult. "Sapporoki" was about one month after harvest. Sensitivity of onion to irradiatian gradually decreased after the dormancy period accompanied by growth of inner bud. At this stage, inhibition of sprouting could not be achieved when the same was irradiated after three months of harvest. Complete suppression of sprouting was observed in onions irradiated with 3 to 7 Krad during the dormancy period.
Usually, harvested onions are dried for two weeks before irradiation. Inhibition of sprouting and keeping quality were attained with the dose of 3 to 7 Krad when freshly harvested oaions were irradiated either before or during the drying treatment for storage.
Irradiation period could be extended by low temperature storage of onion after harvest. Growth of inner bud suppressed at 3-5°C even after three months of storage and the length of inner bud was similar to that of one month old onion. Thus, sprouting was inhibited by irradiation and apical dominence observed for three months from the harvest date when onions were stored at low temperature.
Browning of buds was observed in irradiated onions during storage. This was prevented by low temperature storage and such onions have retained good market quality for one month when transferred from low temperature to ambient temperature.

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We Compared antioxidative activity of melanoidin with that of tocopherol on margarine. In comparison of melanoidin with d-δ-tocopherol under the same weight, melanoidin exhibited less inhibitive effect on autoxidation of margarine than d-δ-tocopherol. Synergistic effect was recognized in a combination of melanoidin with tocopherol. Furthermore, a combination of melanoidin, tocopherol and citric acid showed more antioxidative activity on margarine than that of melanoidin with tocopherol.
Margarine browned with the addition of 0.005-0.01% melanoidin, but did not below 0.0025%. To inhibit the autoxidation of fat in brown colored foods such as biscuit and cookie, the use of xylose or glucose, instead of melanoidin, with tocopherol may be more effective than that of melanoidin with tocopherol.

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The essential oils, methylene chloride extracts of some spices and some citrous oils were employed.
Citrous oils did not prevent slimy spoilage, but these constituents, N-methylanthranilic acid, octylaldehyde and citronellal, showed a little preventive effects. The essential oils of celery, cinnamon and cumin, and the extract of dill showed the considerable effect to prevent the slimy spoilage. The combined effects with sorbic acid or lysozyme were observed in the case of many spice essential oils and extracts.

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A rapid and simple method of gas chromatography was studied to determine lactic acid in fermented milk.
The column employed was PEG-6000(10%) on terephthalic acid solid support (1.5m long glass column), which permits separation of lactic acid without derivatizing it into a volatile compound.
In this method it is not necessary to extract, esterify or trimethyl-silylate the sample. The column temperature was programmed from 120°C to 190°C at 6°C/min. The lactic acid was identified by a GC-MS combined system.
The fermented milk sample was added with sulfuric acid to be 0.1% (V/V) and introduced into the gas chromatograph to determine lactic acid quantitatively.
This method gave good quantitativeness for lactic acid and a long life for the column.

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Effect of γ-irradiation for extending the storage life of mushroom "Matsutake" was investigated. Samples were irradiated by Co-60 γ-ray with the doses of 50-200 krad and stored at about 20°C for 10 days. As the index of cap opening the opening ratio was measured during storage, and the organoleptic properties were evaluated by the taste panels immediately after irradiation. The results were: γ-irradiation reduced the rate of cap opening even at 50 krad; no dose effect was apparent; there were no significant differences in hedonic score between non-irradiated and irradiated ones. These results suggest that γ-irradiation is considerably effective to extend the storage life of "Matsutake".

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