The antioxidative activities of glycerol, xylitol, sorbitol and maltitol were investigated against the autoxidation of linoleic acid in aqueous system and lard added to biscuits.
Although glycerol, sorbitol and maltitol accelerated the autoxidation of linoleic acid in the range of 0.008-0.8M, xylitol exhibited the antioxidative activity at the same concentration.
However, glycerol, xylitol, sorbitol and maltitol showed remarkable inhibition on the autoxidation of lard in biscuits. Especialy, induction period of lard was prolonged about 300 and 500 days with maltitol and sorbitol at 10% level respectively.
Synergistic effect did not exist in a combination of xylitol with tocopherol.

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When soybean protein solution is frozen and stored, protein becomes insoluble after thawing. The insolubilization of protein is promoted by the presence of free SH groups in protein, heat denaturation and addition of small amount of urea before freezing.
The insolubilized protein by freezing is translucent porous mass like sponge. The experiment of this material for mixing in sausage up to 40% in the product revealed that it prevents separation of free water and brought no appreciable difference in texture compared with ordinary sausage.

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With the purpose to increase the yield of the textured protein which was prepared by freezing soybean protein solution, effects of various conditions in the production were studied.
Addition of 2.0 to 2.5×10^-4mol CaCl₂ per g protein to protein solution caused 96% insolubilization of protein after freezing and thawing, resulting in the increase of the yield of the textured protein. Heatiug effects on the amount of SH contents of protein, and maximum amount of SH content was observed after 1min. of heating at 100°C, being its insolubilization by freezing increased compared with longer time heating. Addition of 5×10^-6mol Na₂SO₃ per g protein to protein solution, SH contents of which is less than ordinary one, accelerated insolubilization of protein by freezing. Quality of the textured protein was influenced by freezing rate. When protein solution was frozen very quickly at -70°C, the texture became too fine and weak. On the contrary protein solution which was frozen at -5°C had very coarse texture. To make good texture it is necessary to freeze at -20°C. From these results a standard process of the textured protein making is proposed.

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To make kori-tofu, fresh tofu is frozen and then kept -1--3°C in a storage room for about 3 weeks. During this period called Moya, original tofu changed into unique structure like sponge but it is extremely time consuming. Standing on the viewpoint that ionized SH groups can promote protein denaturation by freezing and cause the formation of spongy structure, present paper deals with practical trials to reduce Moya period.
Blowing of nitrogen gas into soymilk before heating caused the increase of SH groups and promoted to form spongy structure, while blowing of oxygen gas caused the decrease of SH groups and prevented the formation of spongy structure. Addition of 5×10^-4M sodium suifite to soymilk before coagulation also promoted the increase of SH groups and also the formation of spongy structure, consequently, Moya period can be reduced. But this adding amounts is limited by food regulation.
It may be concluded that to reduce Moya period and prepare Kori-tofu in good quality, it is important to make tofu with a care for preventing soymilk from decrease of SH groups.

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Off-flavor of Citrus Unshu juice caused by pasteurization was studied to examine the relation with carbonyl compounds.
2, 4-dinitrophenyl hydrazones of the carbonyl compounds formed from pasteurized juice were separated into twelve fractions by means of silica-gel column chromatography and each of fractions 1, 4, and 12 was rechromatographed with silica-gel thin-layer.
Acetaldehyde, acetone and 2-furfural were identified by means of infra-red absorption spectra and mixed melting method respectively.
Isobutyl aldehyde was recognized presumably by Rf value and coloration of spot on a thinlayer chromatogram.
Although the off-flavor of Citrus Unshu juice brought by heat pasteurization seemed to be attributed partly to those carbonyl compounds, it was suggested from the odor of a substance caught by dry ice-methanol cold trap and liquid nitrogen cold trap that further off-flavor factors were contained in a low boiling fraction.

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The following color stuffs were used in this experiment: Food Yellow No.4, carthamine yellow (Tana color Y), crocin (crude extracts of Gardenia grandiflora), riboflavin and curcumin (Curcumin "Sanei"). Stability of them was examined with several food additives in transparent ampoules and the above color stuffs were tried to utilize to processing of the syrupped chestnuts.
1. Crocin was the most stable among the yellow natural color stuffs, as the results of model ampoule test of aqueous solutions. Stability of durcumine and carthamine yellow was promoted with ascorbic acid, but riboflavin was very unstable.
2. As the results of utilization of the colour stuffs to syrupped chestnuts, crocin and curcumin were the best among the tested stuffs in respect to residual ratio, permiability into peeled chestnuts, distributive ratio among syrup and peeled chestnuts, and the tone of the color. The above two natural color stuffs were expected to be superior to Food Yellow No.4 practical use.

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Noodle (Udon)-making qualities of wheat irradiated with ⁶⁰Co-gamma ray at the dose levels of 20, 50, 100 krad were investigated with flours made from Japanese Norin-61 and with the one made by mixing American D.H.W., W.W. and Australian W.A. ·F.A.Q. in 3:4:4 ratio.
Considerable damage of starch granules by irradiation were estimated from lowered viscosity in Amylogram and increased maltose value. This damage of starch resulted in increased material loss in cooking and inferior physical properties of cooked noodle. Increased dose level of irradiation reflected upon inferior score in sensory analysis, particularly with masticatory feeling. Inferior noodle-making quality of irradiated wheat were well correlated to dose level, where imported wheat was more sensitive than domestic wheat in terms of irradiation effects.

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