The liquors of various green teas were subjected to both chemical analysis and sensual evaluation.
The correlation coefficients between palatability and content of constituents of Japanese Sencha of various grade were significantly positive as to amino acids, catechins and caffeine, and negative as to sugars. However, the coefficients were insignificant as to above substances except arginine in analysis of various green teas containing imported ones. The coefficient became significantly nagative as to catechins in the case of evaluation by certain panel members without specialized tea taster. Thus, the coefficient was variable as change of subject.
From the results of the multiple regressioun analyses, it was indicated that the relationship between palatability and chemical constituents was rather quadratic than linear. Furthermore, it seemed that palatability was more affected by cooperation of various constituents rather than a single one.

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During ripening and germinating, the vicissitude of soybean protein components was studied by starch gel electrophoresis and ultracentrifugation. It was made clear that the 7S component was formed faster than the 11S component during ripening and that the 11S component was digested faster than the 7S component during germinating.
By starch gel electrophoresis (with urea) of each ripening stage, "initial protein" was found only at the early ripening stage as new clear single band on the electrophoretical pattern. Also it was made clear that the initial protein disappeared as soon as new 7S component had come up at the ripening stage and related with the subunits of the 7S component.

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The relation between the browning of potato tubers caused by gamma radiation and cultural localities or the time of irradiation after harvest was investigated, and the change of tyrosine content in irradiated potato tubers was determined. Irish Cobbler potato tubers harvested at seven localities (Kyushu, Shikoku, Kinki, Chubu, Kanto, Tohoku, Hokkaido) were irradiated with doses of 10 and 20 krad 2, 5 and 10 weeks after harvest and the observation of browning was made on the 7th day after irradiation respectively.
When the tubers were irradiated 2 weeks after harvest, the browning showed marked difference among localities. In the tubers harvested in Kinki, Shikoku and Kyushu, more browning was observed in comparison with those of other localities. The tubers harvested in Kanto showed hardly browning. When the tubers were irradiated 5 weeks after harvest, the browning was reduced except for the tubers in Kyushu. In the tubers irradiated 10 weeks after harvest when the tubers egan to sprout, little browning was observed. It is suggested that the suitable time of irradiation after harvest is about 1.5-2 months after harvest.
The tyrosine content varied among localities, and the content was increased by irradiation. The increasing rate of the content was greater in irradiated and browned tubers than in irradiated but non-browned tubers.

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Effect of cathode-ray irradiation on the rheological properties of soybean protein (Na-salt) solution was investigated by Rheometer RM-500 manufactured by Shimazu Co.
As increased dose up to 10 Mrads, hysteresis loop of the gelled 10%-soybean protein was varied, so that comparative dimentions of hysteresis loops and yield values of these irradiated solutions were increased. Relative viscosities of these protein solutions were related with dose, but rheological differences between the soybean protein solution and other solutions containing some additives such as urea, cystein, and ascorbic acid were observed.
In other experiments, intrinsic viscosity of these solutions was determined. As a result, variation of intrinsic viscosity of irradiated solution increased strongly at the dose of 0.5 to 1.0 Mrads. Experimental equation between (R) and intrinsic viscosity[η] was as follow;
log[η]=24.5log(R+5.21)-(21.4±0.6)

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Distributions of nucleotides in black tea of Japan and abroad were investigated by means of ion exchange chromatography on a Dowex 1-X8 column.
As the results of column chromatography of the aqueous extracts, it was found that distribution patterns of nucleotides in several kinds of black tea resembled each other, but were extremely different from those of green tea; 2'- and 3'-isomers of AMP, CMP, GMP and UMP were detected in addition to 5'-ribonucleotides. The presence of guanosine was also recognized.
The result indicates that enzymic degradation of RNA takes place during the process of manufacture.

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Decomposition of pectin or orange juice by mechanical method and the effect of this method on the clarification were investigated.
Impact Cell Mill developed in Kyushu University for the crushing single cell organisms was applied for crushing the pectin substances.
The behaviors of the pectin obtained by this treatment was as same as that of the pectin treated with an acid stable hemicellulase.
The clarification of orange juice with pectinase preparation was acceleated by the preliminary crushing of pectin substance with a machine such as Impact Cell Mill and this method is supposed to be recommended for practical orange juice making.

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The relationships between the delay of the time of gamma irradiation and the sproutinhibition of Sapporo-ki onions were studied, and the nucleic acid content in inner buds of the onions was also determined. The onions were irradiated with the doses of 3-15 Krad and stored at room temperature except for the constant temperature lots of 1°, 6°, and 20°C. Onions which were irradiated 2 weeks after harvest did not sprout completely. However, when irradiation time was delayed about 4 weeks after, the inhibitory effect of gamma radiation on the sprouting was remarkably reduced. In irradiated onions stored 3 weeks after harvest, their inner buds had elongated slightly, and it was similar to the state of inner buds of Senshu-ki onions in budding period. Moreover, a similarity between their inner buds was observed in the pattern of the chromatograms of nucleic acids separated by using MAK column. The contents of s-RNA, r-RNA and DNA of inner buds in irradiated onions decreased by about a half of that in unirradiated onions 2 months after irradiation, and there was no difference between the contents of nucleic acid in 5 Krad onions and in 15 Krad ones.

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