Effect of internal residual air on food quality in retortable pouches was investigated.
1) Deterioration of the contents was directly related to the amount of residual air within the pouch in the case of food packed in aluminum foil laminate.
2) Residual air of 10-15ml per pouch(170×130mm) was desirable to prevent the pouch from bursting when the pouch was sterilized at 120°C under a pressure of 1.4kg/cmcm².
3) It was found that the heating rate and lethality of the pouch varied significantly depending on the amount of the residual air.

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Extraction of phytoglycolipid(PGL)with a 70% ethanol solution under reflux was the most effective condition in the determination of PGL in defatted soybean meals. The extract was dialyzed against water and washed by Folch's method. The PGL remained in the dialysis tube and in the lower phase of Folch's washing. After alkaline hydrolysis, the PGL was determined on the basis of a phosphorus or a sugar analysis in the PGL spot on a thin-layer with silica gel by modified component of chloroform-methanol-conc. ammonium hydroxide-water(10:7.5:1.5:1.5). The PGL content of defatted soybean meals were 0, 075-0.080%.

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The emulsifying capacity(EC)and emulsion stability(ES)of isolated soybean proteins which were partially hydrolyzed by holding them in 0.05-0.10N HCI at 95°C for various durations were compared with the EC and ES of unhydrolyzed soybean protein isolate. The EC and ES of unhydrolyzed proteins decreased to a minimum level in the isoelectric region(around pH4.5)regardless of protein concentration, while those of the partially hydrolyzed proteins showed no decrease in that region and exhibited a remarkably high level throughout the pH range. The effect of partial hydrolysis was especially marked on the ES, e.g., the ES of 34mgN% unhydrolyzed proteins at pH4.5 increased by hydrolysis from a level below 10% to a level of around 80%, and the effect of hydrolysis on the ES was clearly observed even in the condition of high NaCl concentration(0.5M). The partial hydrolysis by dilute hydrochloric acid had high specificity and liberated aspartic acid selectively in the initial stage. The maximum effect of hydrolysis on EC and ES was obtained in the range in which 5-20% of aspartic acid was liberated with no other amino acids being liberated yet. This condition corresponded to 5-40 hours of hydrolyzing time.

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A simple analytical method of vegetable protein products(vp)in ground meat were developed. The polysaccharide components from various vp, which were isolated as precipitates by adding ethanol to alkaline solution of them, showed iodine colour reaction. The polysaccharides from ground meat samples, on the other hand, showed little colour reaction. The starch contents of various commercial vp used in commercial ground meat, showed a range of 0.09-2%. Therefore the method is used only for detecting vp in ground meat which contains uncharacterised vp. Quantitative analysis of vp, however, can be made in cases of the ground meat contains vp of which starch content is known. We applied this method to the ground meat samples with varying amount of soybean protein products and wheat protein products, and got reasonable values with a coefficient of variation less than 4.5%.

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Anthocyanins isolated from two grape varieties, Koshu(cultivated in field)and Gros Colman (cultivated in a green house)were identified as monoglucosides only. The major pigments were consisted of malvidin- and peonidin-3-monoglucosides, and malvidin-3-(p-coumaroyl)-monoglucoside. Petunidin- and delphinidin-3-monoglucosides were found as the minor pigments. Besides, there was an unidentified anthocyanin in Gros Colman.

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Fatty acid composition of the peanut oil was analyzed by gas-liquid chromatography with 28 varieties(16 varieties of Virginia type and 12 of Spanish)grown in the University Research Farm in 1973. Oleic, linoleic, palmitic and stearic acids were the major fatty acids of both types and the former two acids accounted for approximately 80% of the total acids. The ratios of oleic to linoleic acid(O/L)were significantly high in Virginia (average 1.85)compared with Spanish(average 0.95). Strong negative correlations were confirmed between oleic and linoleic acids in both types.

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Soybean was stored for 8 months at temperatures of 30°-50°C. No marked changes were observed in both the color and the rate of water absorption of soybean stored at 30°C for 8 months. After storage at 40°C for more than 4 months, however, the color of soybean darkend and the rate of water absorption decreased. Soybean milk prepared from soybeans stored at 40°C contained less nitrogen and formed softer curd than that prepared from soybean stored at 30°C. The amount of water soluble nitrogen of soybeans tended to decrease during storage. In the gel filtration patterns of water soluble nitrogen fraction of stored soybeans, the first eluted fraction decreased or disappeared after 6 weeks' storage at 40°C or 50°C.

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