An analytical method for Japanese Agricultural Standard of green tea was studied.
First, one group of sencha (common green tea) including high, medium and low grade was subjected to chemical analysis as well as organoleptic test. The correlation coefficients between the content of main green tea constituents, i.e. total nitrogen, tannin (catechins), caffeine, water soluble matter, free reducing sugars and amino acids, and the scores of sensual evaluation, i.e. style, color, aroma, color of liquor and taste, were calculated. Among them that of total nitrogen was the highest on respective evaluation values.
Next, the correlation coefficients between total nitrogen and evaluation values were investigated on other three groups of green tea including commercially packed tea or foreign produced tea.
The total nitrogen content coincided significantly with the quality grade as to domestic tea, although it indicated only degree of style as to foreign produced one.

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The changes of lipid and its fatty acid composition of peanuts treated in hydrogen peroxide (H₂O₂) were studied.
The lipid was extracted with chloroform-methanol (2:1) from shelled peanuts and from sliced peanuts which had been treated with 5% H₂O₂ for 15min. and 60min. respectively, and analyzed by using thin layer chromatography and gas liquid chromatography.
The following changs were observed on the crude lipid of the seeds subjected to H₂O₂ treatment: acid value increased remarkably, peroxide value did not change distinctively and iodine value decreased slightly. A spot was detected on the thin layer chromatogram, which was not found on that of the lipid from the cotrol sample.
On fatty acid composition of the lipid, the contents of oleic and linoleic acid decreased and some substances which had relatively long retention time were detected. These substances were found in the free fatty acid, diglyceride and unidentified fractions, but not in the triglyceride fraction. The relative retention time of some of these substances decreased somewhat by acetylation.

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An enzyme levanase (levan depolymerase) from a strain of Streptomyces griseus was purified. The enzyme in cultivation broth was concentrated about 300 times through the treatments such as DEAE-Sephadex adsorption, salting out with ammonium sulphate and gel filtration with Biogel. Purity of the enzyme was certified from the results of polyacrylamide-gel electrophoresis and sedimentation pattern of ultracentrifuge.
The optimum reaction temperature was about 50°C and the enzyme was stable at temperatures under 50°C. pH optimum of the reaction was observed to be at 6.5 and pH stability was found at pH 6-8. The enzyme was reactive on levan produced by B. subtilis, but not on sucrose, raffinose, inulin and dextran. The enzyme reaction was inhibited by the presence of the materials such as pCMB, Cu, Ni, Mn, and Zn ions, especially by pCMB and Cu. On the other hand, the presence of Mg ion was found to activate the reaction.
Michaelis constant was calculated as 0.0073g/ml. Molecular weight of the enzyme estimated by gel filtration was 45000 and its sedimentation coefficient (S20.w) was calculated to be 4.75S.

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The effects of heating temperature and time during processing on color, amino acid, organic acid, ascorbic acid, sugar and uronic acid in tomato juice were studied. The variety of tomato used in this study was Heinz 1370. The juice was extracted, and a part of it was frozen, the other parts were held at 90°C for 10, 40 or 90 minutes and then sterilized at 110°C for 84 seconds or at 121°C for 42 and 168 seconds.
As heating temperature became high or heating time was long, decrease of lycopene and ascorbic acid, and increase of serum color were observed. The rate of decrease of lycopene was especially rapid when the sterilization temperature was high, and decrease of ascorbic acid and increase of serum color were rapid either holding at 90°C or sterilization at above 100°C. Total amino acid content decreased and the decrease of threonine was remarkable. Glutamic acid decreased slightly, but the percentage of it in total aminoa cid increased. Peptide content obtained by dialysis did not change, but average peptide length changed from 4.36 to 3.77. Pyrrolidone carboxylic acid increased and malic acid decreased slightly. No difference was found in sugar components. Galacturonic acid decreased obviously.

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The struvite-like crystal substances were separated from soysauce prepared from mieki.
The crystals were identified as struvite seen occasionally in tuna can as the results of components analyses and infrared absorption spectrometry. The magnesium and phosporus contents of mieki and soysauce were determined and struvite formation at some pH values were discussed.
Contents of these components were enough for crystalization of struvite in soysauce, but the most important factor was the pH value of the soysauce. It was necessary to prevent the struvite formation, to keep the pH value of soysauce under 6.0.

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In spite of the unstability of carotenoid pigments, the color of the red pepper, Capsicum annum, is preserved for a long time even in the dried state. This suggests the occurrence of some antioxygenic substances in Capsicum.
In order to determine the effective compounds, Capsicum was extracted with chloroformmethanol (2:1) and water and the antioxidant activity of each fraction was estimated by oven test method.
The antioxygenic substances were found in lipids fraction and the active substances were divided into two fractions by silicic acid column chromatography. By thin layer and gas liquid chromatographies, antioxygenic substances in Capsicum were identified as α-tocopherol and cap- saicins. Capsaicins were known as the pungent principles in Capsicum, but the antioxidant activity has not been reported.
It was also proved that both of these substances were effective to the preservation of the carotenoid pigments of Capsicum (capthanthin and capsorbin).

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Organic base fractions of Soy Sauce were isolated by Amberlite IRC-50 column (pH 4.5), and identified with thin layer chromatography. 1) Organic base fractions obtained from Soy Sauce were about 18% of total nitrogen, of which major components were basic amino acids. 2) Phenylethylamine, tyramine, histamine, cadaverine and putrescine were identified. Besides those five amines, five ninhydrin positive spots (unidentified) were detected by thin layer chromatography. 3) By sensory tests, it was indicated that the organic base fractions contributed to the bitterness and astrigency in Soy Sauce.

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