It has been known that garlic contains antioxidative compounds. To know the antioxidative substances, as the first experiment, sulfur-containing compounds were separated from the extract of boiled garlic by ion exchange column chromatography and these compounds showed antioxigenic effect. Antioxidative activity of boiled garlic and S-allyl-L-cysteine sulfoxide were decreased by the enzymic action of garlic. Synergistic effects of separated sulfur compounds to soybean protein hydrolyzate and d-δ-tocopherol were not demonstrated. Antioxidative activities of three groups of authentic sulfur compounds, namely, A group: mercaptans, monosulfides and disulfides, B group: S-allyl, S-propyl and S-buthyl-L-cysteine, C group: S-allyl, S-propyl and S-buthyl-L-cysteine sulfoxide, were compared. Among them, S-allyl-L-cysteine sulfoxide, S-propyl and S-buthyl cysteine showed strong antioxigenic effect which increased in that order.

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Few information has been available to the analytical procedures and content of propylene glycol in foods. Analytical procedure of propylene glycol by gas chromatography was investigated, and the propyllene glycol content in 150 varieties of commercial foods was analyzed. Propylene glycol in some foods was indentified by gas chromatography-mass spectrometry. The propylene glycol content in foods was in the range of 1, 021 to 27, 611 ppm for the purpose of increasing water coating ability and for the solvent of various food additives in the range of 32 to 985 ppm. Noodles (10g) containing 2.4mg of propylene glycol were boiled for 2min at 95°C, and 1.32-1.80mg (55-75%) were lost in water.

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The volatile concentrates of a stone-milled buckwheat flour were prepared by a continuous distilation-extraction appratus and the components were isolated and identified by gas chromatography and mass spectrometer. Following 45 compounds were found; 13 alcohols, 6 aldehydes, 6 methyl ketones, 2 esters, 6 aromatic hydrocarbons, 7 alkanes and 5 other compounds. On the other hand, seven flour fractions were obtained by roller-milling and their volatile components were investigated. First three fractions consisted of mainly endosperm, and second three had high contents of testa and embryo. The last one was mainly pericarp. The best evaluation score for flavor was obtained for fraction 4 and the second for fraction 5. The major 13 peaks of the volatiles were further investigated. Gradual increase was observed in the amount of n-alkyl alcohols and salicylaldehyde from fraction 1 to 6, and this was extreme for fraction 7. But two peaks containning either n-hexanal or n-nonanal, 2-octanol and n-tetradecane were higher for fraction 3 and 4. These distributions may be related to the evaluation of flavor.

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Compound lipids were fractionated from the total lipids in meat and viscera of horse mackerel Trachuras japonicus in all seasons by means of silicic acid column chromatography and thin layer chromatography (TLC). Each compound lipid was identified by TLC by comparison with the stantard phospholipids and by color reactions with some reagents. The fatty acid composition of each compound lipid was determined by gas-liquid chromatography. The results obtained were as follows: (1) The compound lipids were fractionated into nine lipids in each part of horse mackerel. These were phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), cardiolipin (CA), sphingomyerin (Sph) and others. (2) The total amount of compound lipids was almost constant through the year in each part of horse mackerel, shown as 500 to 600mg% in meat and 430 to 520 mg% in viscera. (3) The main compound lipids in meat were PC (44.6-56.3%) and PE (15.6-22.5%), and both decreased in summer. On the other hand, the main compound lipids in viscera were PC (26.6-38.9%), CA (18.7-26.0%), Sph (9.9-14.6%) and PE (8.9-16.6%), and PC and PE decreased fn spring and summer. (4) The fatty acid composition of each compound lipid was considerably different, but these seasonal variation was similar; the saturated and monoenoic fatty acid content (%) was higher in summer, on the contrary polyenoic fatty acid content was lower in summer in meat, but the content of the above fatty acids was almost constnt through the year in viscera.

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In previous papers, we studied on the over-all cooking-rate equations of foods. In this paper, we have studied on the over-all drying-rate equations of various-shape potatoes. The drying-rate equations were postulated in two types: one was a simple nth-order rate equation and other was a similar rate equation based on the shrinkage models.
dx/dθ=k_n(1-x)ⁿ; n=0.6-0.8
dx/dθ=k_nS(1-x)ⁿ; n=0.3-0.6
x=(W_o-W)/(W_o-W_e)
where, x: drying ratio (-), 0: drying time (min), W, Wo and We: intermediate, initial and equilibrium water contents (g-H₂O/g-D.M.), S: drying surface area (cmcm²).

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This study was started with the purpose of effective utilization of raw materials and coloring control of fermented food. In order to clarify the function of hemicellulase of koji molds, xylanase activity of isolated koji molds from various mold starters was investigated. The results obtained were as follows: (1) The best conditions to determine the xylanase activity of koji molds were to incubate the mixture of enzyme and substrate in a buffer solution at pH 5.5 for 30 minutes at 40°C. (2) Formation of xylanase by mold was attained when the wheat bran moistened with 60% water and cooked was cultivated at 30°C, and the enzyme activity was rapidly increased in 40-60 hours reaching the maximum activity in 70 hours. (3) Xylanase activity of koji molds was considered to be the inherent characteristic of each mold. (4) Relatively high correlation was seen between xylanase activity and neutral-protease or alkaline-protease activity.

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We studied histological view, using an adhesive tape, in a germinating rice seed. To get clear figures of starch granules and starch tissues, we compared two adhesive tapes, Cellotape (Nichiban, Inc., Tokyo) and Scotch Brand Tapes (3M Philippines, Inc.). The adhesive tape was contacted to the smooth surface of a germinating rice seed to copy bared starch granules on it. The smooth surface was made by a microtome. In this comparison the Scotch Brand Tapes showed excellent quality. Starch tissues in the endosperm were eroded from the part attached to the epithelium of scutellum, and in the scutellum starch granules were accumulated. The starch granules in the endosperm were angular in shape, but at the partially eroded starch tissues in the endosperm, the starch granules became roundish and smaller.

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Three yellow pigments (Y1, Y2 and Y3) were isolated from salted radish by sephadex G-25 column chromatography and paper electrophoresis. Two of them, Y1 and Y2, were purified by thin layer chromatography. Y1 showed almost the same absorption spectrum as Y2. Both pigments had their absorption maxima at 405nm and were presumed to be nitrogen-containing compounds from the color reaction with Dragendorff's reagent. Y3 was not purified, but had no absorption maximum in the visible region of the spectrum.

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