Several essential oils, components of these oils, and three vegetables (welsh onion, chinese garlic and ginger) were tested for their antioxidative effects on both dehydrated model based on carboxymethylcellulose and dehydrated pork. Samples treated with each materials mentioned above by various means were packed in cans under an atmospheric pressure after freeze-dehydration. The cans were stored at 37°C and the rancidity of the contents was measured at intervals by thiobarbituric acid and peroxide value test or by the oxygen analysis of the head space. Both clove and thyme oil exhibited apparent antioxidative effects and similar results were obtained with eugenol and thymol, the major components in respective oils. When the model system or pork was dehydrated with welsh onion or garlic which was placed separately on the same shelf of the dryer during dehydration, the process of oxidation was retarded even in the absence of welsh onion or garlic themselves in the cans. However, much higher effects were obtained in cans packed with dehydrated welsh onion or garlic, and the addition of allyl sulfide or allyl disulfide prior to the dehydration revealed the highest antioxidative effects. With ginger, the effect was lower than with welsh onion or garlic, but the addition of the components of ginger, shogaol and zingeron, proved to have an excellent antioxidative effect comparable to that of allyl sulfide or allyl disulfide.

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The effects of storage temperature and moisture of tea were recognized to show the most significant effects on the qualities of tea during storage. Although significant on the aroma, taste and the color of the water-extract, the effects of the oxygen content in the head space of the cans in which teas were stored was almost insignificant on the browning of tea so far this experiment concerned. The color of the water-extract and the taste of tea well correlated with the content of ascorbic acid which was affected by the temperature and moisture content as well as oxygen content.

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Sencha (ordinary green tea) of high, middle and low grade, and Gyokuro (finest green tea) were subjected to chemical analysis as well as organoleptic test. Three grams of tea were infused three times with 180ml of boiling water for the test. The correlation of the chemical analysis on catechins, amino acids, caffeine and soluble matter with the results of organoleptic test on the liquors were studied. The results of organoleptic test by fifteen panels indicated that the first infusions of sencha of high and middle grade, and Gyokuro were significantly flavorous, while the third infusions from all of samples were poor. The desirable liquors were rich in various constituents including catechin gallates, caffeine and amino acids, and showed compraratively high rate of amino acids to other constituents.

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When 3×10^-3 M L-ascorbic acid (AA) and erythorbic acid (EA) in 50ml of 3.6×10^-3 M HCl solution (pH 2.3) containing 3×10^-3 M Fe₂ (SO₄)₃ were treated in the oxygen gas flow at a rate Of 3.3ml/sec. at 25°C, the amounts of remained AA and EA after 20min were 79.6 (±2)% and 3.7 (±0.5)% of the initial amounts respectively.
The effect of ferric ion on the decomposition of AA and EA was remarkable and accelerated definitely by lowering the pH value to 1.4.
The rate of the decomposition of these acids was also affected to some extent by the presence of neutral salts in the reaction mixture.
The difference of the decomposition rate between AA and EA is so definitely and highly reproduciable that a potential of a new method of simultaneous determination of these acids within the level of 2.5×10^-3 to 3.5×10^-3 M was suggested.

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A series of black tea samples classified high, middle and low grades was selected from various countries of origin. The correlations of theaflavins and thearubigins contents with the results of tea taster's evaluation of these samples were studied.
Theaflavins content or the ratio of theaflavins to thearubigins showed high positive correlation with the evaluation of lquality, especially color and taste, whereas thearubigins content had not any correlations with tea taster's marks. Furthermore, it was assumed that theaflavins and thearubigins were likely to form predominantly color of black tea liquor from the result of multiple regression analysis.

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After long storage, Kori-Tofu changes its color into brown from cream with developing off-flavor. As the result, the phospholipids were almost decomposed, although phosphatidylcholine was found to remain.
In order to make clear the substances from autoxidized phospholipids, aliphatic carbonyl compounds were examined. With respect to n-alkanal, n-ethanal (acetaldyde) was identfied, and was the largest in quantity in all carbonyl compounds. In 2-alkenal, three kinds of compounds were detected. One of them was estimated as 2-butenal (crotonaldehyde), and other compounds were observed to be composed of more five carbons. In 2-alkanone, three of compounds were detected, two of them were estimated 2-nonanone and 2-octanone. In dienal, one kind of compound was detected.

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Volatile fatty acids and alcohols which were produced from the phospholipids by autoxidation were examined by gaschromatography and thin layer chromatography. The following compounds were characterized; acetic acid, propionic acid, iso-butilic acid, n-butilic acid, n-valelic acid, methanol, ethanol, propanol, iso-butanol, n-butanol, iso-pentanol, and n-pentanol. Acetic acid and ethanol were the major components, and showed 94% in a total fatty acid and over 98% in a total alcohol, respectively.

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The separation of L-ascorbic acid (AA) and erythorbic acid (EA) was investigated by thinlayer Chromatography. AA and EA were clearly separated by the employment of water saturated methylethyl ketone as developing solvent. Optimum concentration of EA and AA for separation was within the range of 0.04-0.05%.
The developing time was far more reduced than that of ordinary paper chromatography.

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