Proteolipids in processed soybean foods, such as Tofu (soybean curd), Natto (fermented soybean) and Koritofu (dried bean curd), were separated from the chloroform extract of their defatted samples by fluff formation after dialysis against chloroform-methanol followed by water. The yields of proteolipids) were about 0.05% and a single spot was obtained on a thin-layer chromatogram.
Analysis of phospholipid component of the lipid moiety showed that phosphatidylcholine and unknown phospholipids, at near original point on TLC, were the major components. The major fatty acid component of the lipid moiety was palmitic acid, contrary to linoleic acid in soybean phospholipids. The amino acid allalysis showed that the more hydrophobic amino acids and less acidic amino acid than those of a soybean protein.

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Miso (fermented soybean paste) is often used as seasoning in the form of concentrated suspension. The author investigated on the viscosity of the Miso suspension from the viewpoint of cooking science. The results obtained are summarized as follows.
1. Viscosimetric properties of various Miso samples were examined in ralation to concentration and temperature.
2. The suspension of Mame-miso (Miso: water=100:90-100) showed the negative shear thixotropy. It seems that this condition of suspension might be in the range of viscous property from concentration dependency and hysteresis loop. It was furthermore thought that the component taking part in flow property might be proteinous nitrogen having solvation ability from the viscosimetric behaviors under several pH and temperature conditions.
3. In the case of Kome-miso suspension, adequate water content for the viscous property range might be 20-60% (Miso=100) in Shiro-miso and 20-70% in Sendai-miso. Discussion was also made on the influence of sugar on the viscosity.

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Some factors affecting the emulsifying properties of water extract, acid-precipitated protein and whey from defatted soybean meal were studied, and the following results were obtained: 1) Emulsifying capacity and interfacial tension decreased, and emulsion stability increased respectively with the increase of protein concentration. 2) Emulsifying properties of water extract and acid precipitated protein were remarkably affected by pH and minimum values were obtained at isoelectric range; on the contrary, whey was hardly affected by pH, and gave high values throughout the pH range. 3) Emulsifying properties of water extract and whey decreased slightly by heat treatment, but those of acid-precipitated protein were hardly affected by heating the protein solution. Jelly strength of emulsions from water extract and acid-precipitated protein increased by heating above 70°C. 4) Emulsion stability and jelly strength of emulsions clearly increased by the addition of sodium chloride, but emulsifying capacity increased only slightly.

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The texture and forming process of yuba-film made from soybean proteins were studied to discuss on the mechanism of film formation. The yuba-film containing 60-80% of moisture was observed by a scannig electron microscope after freeze-drying. The upper side of this material consisted of a high textured layer wich showed no traces of ice crystals by freeze-drying, and the lower side consisted of a low textured layer which took a porous shape. In Millon and xanthoprotein test, clear difference in color reactivity was observed the surface of yuba-film, the back and heat-induced gel. These results suggested the difference of texture between yuba-film and heat-induced gel.
The layer which formed on the gas-liquid interface in the earlier stage was replaced by various solid phase such as films of acetylcellulose, cellophane etc. Yuba-like films could be formed on these solid-liquid interfaces if the moisture permeability on the solid phase was higher than 0.049mg/cmcm²·min. The yuba-like film formed on the interface of cellophane and solution had similar texture, high strength and no wrinkles compared with the conventional yuba-film.

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In view of the growth of ice crystals in the freeze concentrating process of Satsuma mandarin (Citrus unshiu MARC.) juice, freezing process of orange juice with one direction heat flow was observed by microscopy to discuss about; (1) ice length and freezing condition, (2) crystal formations of frozen orange juice and interfaces of crystal growth.
In the process of freezing of orange juice, an ice length at first equilibrium existed contrary to the Stefan's theory observed at freezing of pure water. The constituent (sugar) of frozen juice were concentrated between ice crystals, however, that of unfrozen residue were not. As the productivity of concentrated juice depended upon the ice length or the cooling time, the acquired equations from this experiments must be useful to determine the cooling time. The figure of the crystal tended to be more minute as the temperature was lowered and the concentration of the juice increased. Furthermore, fernlike crystals were observed in higer concentrations (40, 50°Bx) under low freezing rate.

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Heat-induced off-flavor of satsuma orange juice was investigated by headspace gas chromatography. Behavior of dimethylsulfide in low boiling components was considered to deeply relate with off-flavor induced by heat treatment of satsuma orange juice.
The amount of heat-induced dimethylsulfide in headspace gas was sharply increased by the addition of segment covers or albedo to the satsuma orange juice.
Volatility of authentic dimethylsulfide was very high (almost 100%) in distilled water as well as in the juice without segment covers or albedo, though the volatility was depressed to about a half in the both juices with segment covers and albedo.
Heat-induced off-flavor was organoleptically recognized when dimethylsulfide was more than 0.2 ppm in headspace gas of closed vessels.

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The relation between the development of volatile compounds and the lipid degradation of tomato fruits during after-ripening were studied.
When fruits were harvested at mature green stage and stored at 20°C, contents of volatile, and aliphatic carbonyl compounds and volatile fatty acids remarkably increased at the light pink stage, 3-5 days after harvest, comcomitantly with development of volatile compounds. On the other hand, unsaturated fatty acid contents of free fatty acid fraction in tomato fruits decreased markedly at the light pink stage and after that tended to increase.
Activities of lipolytic acyl-hydrolases, particulally phospholipase and galactolipase, and lipoxygenase that decompose unsaturated fatty acids of tomato fruits were the most intensive at the light pink stage. accounting for the biosynthesis of volatile compounds at the light pink stage.

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The browning reactions in green tea infusion during heating were investigated. Green tea infusion was remarkably browned at the temperature above 80°C for several hours. The major parts of browned components were not extraeted by methyl isobutyl ketone and butanol, and remained in an aqueous phase.
The contents of four catechins such as(-)epigallocatechin galiate, (-)-epicatechin gallate, (-)-epigallocatechin and (-)-epicatechin, and ascorbic acid in green tea infusion were remarkably decreased during heating, while the contents of amino acids and reducing sugar were not changed.

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