Changes in starch and sugar contents and in enzyme activities related to gluconeogenesis and amylolysis during the process of after-ripening in chilling-injured banana fruits were compared with those of healthy fruit.
In the healthy fruits, a linear increase in sugar contents and a sharp decline of starch contents started on the 6th day of storage at 20°C, accompanying with increase in phosphofructokinase (PFK) activity. While apparent fructose-1, 6-diphosphatase (F1, 6 DPase) activity stayed relatively low and constant level.
In contrast, a gradual increase in sugar contents accompanying with a remarkable increase in apparent F1, 6DPase activity but no significant change in starch contents were noted in the fruits stored at 6°C.
Storage at 20°C after the storage at 6°C for 9 days caused a rapid increase in sugar contents and sharp decline of stach contents within 5 days. In these chilling-injured fruits, however, a low PFK activity and a remarkably high apparent F1, 6DPase activity were noted throughout after-ripening.
These findings suggested that, in chilling-injured fruits, an increase in gluconeogenesis occurred preceding to after-ripening and an increase in amylolysis also occurred during the process of after-ripening.

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The internal wall corrosion of canned asparagus accompanies no sulfur stain, and obviously differs from that of canned orange juice.
Fresh asparagus has been analyzed in our laboratory as to its amino acid composition in relation to the internal wall corrosion of canned asparagus, and it was shown that one of the corrosion factors of canned asparagus is considered to be a compRund of glutamic acid and organic acids.
In order to ascertain the corrosion factors of tomato fruit, investigations were made on its amino acid composition as well as on the relation between the composition and corrosion of internal wall of the canned plant.
Tomato fruit was extracted with 75% ethanol. Glutamic acid was found to be the major component among amino acids. The extracts were fractionated with ion exchange resins and acid fraction "A-2" was partially hydrolyzed for 2 hours at 100°C with 2.4N HCl, and the hydrolyzate was further fractionated with cation exchange resin. The corrosive activity of each fraction was examined.
The corrosion factors of tomato fruit are adsorbed to anion exchange resin (OH^- form), but not to cation exchange resin (H⁺ form). From resin analysis and paper chromatography, it is concluded that the corrosion factors in tomato fruit are acidic substance and one of them is a conjugated compound of glutamic acid and organic acids.

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Mustard and horseradish flours and 'Wasabi' powder were investigated by headspace gas chromatography. The Rg (ratio of the peak area of iso-propyl isothiocyanate to that of 3-butenyl isothiocyanate) values of pressed mustard flours and that value of mustard flour prepared with an expeller press were large, but these values of mustard flours made by the extraction with solvent were small.
In horseradish flours, the Rg values of the samples from Hokkaido were large, and that of one from Nagano prefecture was small. The Rg values of these two flours expressed linear relation with the amount of sample for determination. 'Wasabi' powders for experiment were prepared from mixing mustard and horseradish flours in a certain ratio. Rg values of the 'Wasabi' powders were differed by the combination ratios, but the relation between Rg values and combination ratios was shown with a hyperbola curve.
In the hydrolysates of spiceries collected from market, iso-propyl isothiocyanate was not detected. However, the volatile component which had retention time earlier than that of this isothiocyanate was detected. Therefore, whether the spicery was blended in 'Wasabr' powder or not would be distinguished by this method.

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Effect of center temperature of sausage during cooking on its viscoelasticity was investigated in the manufacturing process of hen-meat sausage. Center temperature of sausage was measured by a thermometer with a thermocouple, and breaking stress, viscosity, elastic modulus in the center of sausage by a curd meter.
Center temperature of leg-meat sausage needed longer times to rise and reach to a certain level than that of the breast-meat sausage needed. The reason would be due to higher fat content in leg-meat.
Four minutes were needed till elasticity appeared in the center of breast-meat sausage when processed at 80 or 95°C, and six minutes when processed at 65°C. During these heating process, center temperature of sausage rose to 40°C or more. This temperature corresponded to the coagulation temperature of myosin B. On gelation of sausage, at first step, viscosity increased and then elasticity appeared. It was deduced from viscosity increase that polymerization of myosin B by cross-linking or entanglement occurred. The presence of network structure with cross-linking was deduced from elasticity appearance.

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The effect of radiation with a dose of 0-5 Mrad on rice starch as a function of its water content has been investigated by particularly studying the changes of formed radicals by ESR and physicochemical properties. In case of 10 Krad irradiated starch in 1 to 8% (dry basis) moisture, the signal of radicals was a singlet, but at 30 Krad in 15 to 30% moisture, the signal showed a complex pattern. Their radical ocntents decreased by the increase of moisture content. At 1 to 8% moisture contents level, radicals formed considerably larger than that of 15 to 30%. It was found that the water molecule was considered to have a role of protective effect. Thus, the similar tendency was observed in the cases of intrinsic viscosity, mean degree of polymerization, iodine affinity and content of carboxyl group. As to stability of radicals, the radicals in 1 to 5% moisture contents were kept considerably stable for 24 hours. But, the radicals in higher moisturecontents were unstable and the radical contents decreased more fastly by the iacrease of moisture content. In more than 11% moisture contents, the radical contents decreased rapidly just after exposed in air.

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The formation of lysinoalanine, N⁶-(DL-2-amino-2-carboxyethyl)-L-lysine, on alkaline treatment was investigated. Changes of basic amino acids and cystine during alkaline treatment at different pH, times and temperature, were analyzed with an amino acid analyzer.
The results show:
1) Lysinoalanine was formed depending on pH, temperature and time on alkaline treatment. The higher pH, temperature and time, the higher amount of lysinoalanine was recognized.
2) The formation of lysinoalanine seemed to be related to cystine in proteins. In 11S protein having higher content of cystine than 7S protein, the higher amount of lysinoalanine was recognized.
3) The formation of lysinoalanine was slightly recognized in soybean products.

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To investigate the effect of protein denaturation of soybean milk on the properties of Tofu from the milk, physico-chemical changes of soybean milk protein were studied. Soybean milk was prepared under different ratio of water to soybean and ionic strength. Protein aggregation was shown by measurements of viscosity and turbidity. It was found that the aggregates were formed from subunits which were produced from the protein. Formation of the aggregates are promoted by high ionic strength and low ratio of water to soybeans. Those conditions favorable for aggregates formation tend to make the Tofu made from the milk by coagullant hard.

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The effect of size of seed on the oil content and fatty acid composition of soybean seeds of 11 varieties in U.S.A. and 10 samples in China has been investigated. Soybean seeds were sieved to obtain the 3 sizes of seed, i.e. size 1 (large), size 2 (medium) and size 3 (small). The ratio of size 1, 2 and 3 showed 32.9, 38.8 and 28.3% respectively in U.S.A., and showed 32.2, 34.0 and 38.8% tespectively in China. The U.S.A. samples, as compared with the Chinese samples, were higher about 10% on the oil and oleic acid contents and lower about 17 to 28% on linolenic acid content, whereas significant difference was not observed on linoleic acid content. When the size of seed decreased, the oil and oleic acid contents also decreased but the linoleic and linolenic acid contents increased. The increasing ratio of linoleic acid was extremely low. From the results of analysis of variance, the oil content and fatty acid composition were influenced by the variety (sample), and the oil, oleic, linoleic and linolenic acid contents were also influenced by the size of seed. On the correlation between oil and fatty acid contents, the oil content was positively correlated with the oleic and linoleic acid contents, and negatively with the stealic and linolenic acid contents. On the fatty acid pairs, the negative correlations were shown between the linoleic acid content and the palmitic, stealic, oleic or linolenic acid content and between the oleic and linolenic acid contents.

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