In order to obtain the knowledge for establishing the method to prevent the deterioration of the dried material or the flour of Antarctic krill (Euphausia superba), oxidation pattern of the fats was estimated. Results were summarized as follows. (1) In spite of the high ratio of polyunsaturated fatty acids, the progress of oxidation of the krill fats was very slow. (2) It was chracteristic that POV of the krill fats were zero under the experimental conditions. (3) POV of linoleic acid containing the krill fats was kept to be zero when heated at 100°C for 90min. This fact shows the existence of antioxidative substance in the krill fats. (4) The krill fats contained about 200 or 350μg/g·oil of α-tocopherol. But, α-tocopherol has little antioxidant activity on the oxidation of linoleic acid. (5) Methanol fraction obtained from silicic acid column chromatography was determined to be only one which showed antioxidant activity.

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Surface color is one of the important factors for grading the quality of tomatoes. This work was made in order to develop a technique for measurment of whole surface color of tomatoes. A laboratory spectrophotometric instrument with integrating sphere was made for this work and used to measure the relative reflectance characteristics at the three parts of apex, cheek and cavety shoulder of individual fruit. New color index I₃ for tomatoes was presented as follows: where AR₆₆₀, AR₆₂₀ and AR₅₅₀ are average of relative reflectance of both the apex and cavety shoulder in wavelengths of 660, 620 and 550nm respectively. There were high correlations between this color index I₃ and contents of chlorophyl and carotenoid in the peel of tomatoes. The index I₃ was proved to be useful by indicating the changes in average surface color during ripening of tomatoes.

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As the first step of making clear the mechanism of chilling injury of apples, fatty acids composition of neutral lipid fraction, conjugated lipid fraction, phosphatidylcholine and lysophosphatidylcholine in the pulp was investigated in terms of varieties and storage time. As the result, following facts became apparent. (1) The ratio of unsaturated fatty acids to total fatty acids of Ralls Janet which is resistant to cold temparature was higher than that of Starking Delicious which is sensitive to cold temparature. (2) In the case of Starking Delicious, the content of unsaturated fatty acids increased after two and four month storage. On the other hand, the content of Ralls Janet decreased after two months, but increased after four months. (3) The ratio of conjugated lipid to the total lipid of both Ralls Janet and Starking Deliccious was about 80%. (4) In the case of Starking Delicious, the ratio of unsaturated fatty acids to total fatty acids decreased in proportion as the degree of ripeness advanced.

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In order to produce excellent flavoring substances from chicken bone protein by enzymatic hydrolysis, the hydrolytic features, the flavors of hydrolysates and the properties of insoluble fractions after proteolysis were investigated. Of the chicken bone protein fractions, sarcoplasmic protein fraction (26% of total protein) could be easily hydrolyzed by endopeptidase preparations and the hydrolysates were palatable with out remarkable bitterness, while the hydrolysates from myofibrillar protein fraction (10%) were of strongly bitter taste. AS stroma fraction (56%) could not be well hydrolyzed, taste of the hydrolysates was generally weak, although the hydrolytic ratio was increased by the heat treatment at 95°C. By the combined use of an endopeptidase and an exopeptidase, a flavoring substance was obtained in high yield from the heat-denatured chicken bone protein. Its main component was peptides, of which molecular weight was lower than 5, 000, and the taste of the hydrolysates was slightly bitter. But the bitter taste almost disappeared by blending with HVP. It was presumed that the insoluble fraction remained after the enzymatic hydrolysis was a complex of lipids and such proteins as keratin or elastin.

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Effects of the temperature during post-harvest ripening and storage on the behavior of antocyanin and polyphenol in white peaches (Sunagowase, Ohkubo and Koyohakuto) were studied. The quantity of antocyanin increased as the ripening temperature rise until 35°C, and it showed a maximum at 35°C in any cultivar, but at 40°C the red colour was remarkably controlled, and in Ohkubo cv. the redness almost disappered by six days' ripening. Little changes in antocyanin during cold storage were observed, but constant relationship was not given between the storage temperature and antocyanin content. Polyphenol content changed considerably during ripening, and the aspect greatly differed among cultivars. The correlation in the changes of antocyanin and polyphenol could not be recognized in both ripening and cold storage stage. In order to ripen white peaches for processing, the peaches should be kept at the cool rooms below 30°C to prevent the strong appearance of antocyanin.

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Activities of Nitrate reductase, nitrite reductase, some dehydrogenase and glutamine synthetase in Spinach (Spinacia oleracea LINN. cv. new asia) and spuash (Cucurbita moschata DUCH. cv. kogiku) were examined in relation to changes of nitrate contents during storage of these materials. The methods to maintaine the activity of nitrate reductase were also investigated in order to reduce nitrate content during storage of spinach. (1) There were no significant changes in nitrate content of spinach during the storage, and the activity of nitrate reductase declined markedly at the earlier period of storage. On the contrary, nitrate content of squash decreased gradually at the earlier period of storage and decreased sharply at the later period of storage. The activity of nitrate reductase of squash increased gradually during the storage. (2) Activity of nitrite reductase was almost constant in both spinach and squash during the storage. (3) Some dehydrogenases which form the cofactors NADH or NADPH, used by nitrate reductase or nitrite reductase, were analyzed in both materials during the storage, In spinach, activities of glucose-6-phosphate dehydrogenase, malic enzyme, glyceraldehyde-3-phosphate dehydrogenase and glutamine synthetase except for glutamate dehydrogenase decreased during the storage. On the other hand, in squash, the activities of dehydrogenases increased except for glutamine synthetase during the storage. (4) Effect of ambient gas or film-package on the nitrate content during the storage of spinach was as follows: The treatment of 100% CO² and the packaging with polyethlene bags did not affect the change in nitrate content. The treatment of N₂ (100%) reduced nitrate content in leaf blade of spinach and kept nitrate reductase high, but the slight accumulation of nitrite was observed. (5) The treatment of propyl alcohol (1%), N⁶-BA (0.1mM), and cyclic AMP (0.1mM) inhibited the decrease in nitrate reductase activity during the storage of spinach.

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A direct flameless atomic absorption spectrophotometry using a graphite furnace atomizer for the the determination of iron in liquid foods, such as vinegar, sake, wine and beer was described. The concentration of iron was calculated by the addition of an internal standard by measuring the absor-bance of iron at 372.0 nm. Results by this method agreed well with those obtained by a conventional flame atomic absorption method after APDC-MIBK extraction.

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