Antioxidant activities in the methanol soluble fraction of the rind and the content of 12 kinds of fruits, 37 vegetables and 7 others, were examined by the inhibitory effect on the formation of the peroxide from methyl linolate in the test tube at 50°C. Among these samples the epicarp of avocado showed the strong antioxidant activity. It corresponds to about one third of the activity of green tea, rosemary or sage which are already reported with their strong antioxidant activities. Besides, the activity was observed in the followings: a flower of the butter bur, yellow and out layer of onion, red pepper and dried laver. The main antioxidant component in the epicarp of avocado was isolated in the eluate with CHCl3-ethylacetate (1:1) by silica gel column chromatography after the extraction with methanol, water and then ethylacetate, and it was determined to be l-epicatechin on thin layer and paper chromatographies.

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The samples used in this experiment were fresh tea leaves, crude green tea, green tea prepared by heating at 130°C for 30 min (130°C-heated green tea, representing refired green tea), and green tea prepared by heating at 170°C for 30 min(170°C-heated green tea, representing roasted green tea, i.e. Hoji-cha). Crude lipids were extracted with CHCl₃-MeOH (2:1), and separated into three lipid fractions by a silicic acid column chromatography using three solvent systems. Thin layer chromatography was carried on these fractions. After being sprayed with 50% sulfuric acid and heated, the amount of lipids on the plates was measured densitometrically. The total lipid content decreased during the manufacturing process of green tea. Those of crude green tea, 130°C-heated green tea and 170°C-heated green tea were respectively 85%, 70% and 60% that of fresh tea leaves. The lipid fractions which decreased notably during the manufacturing process were glycolipids and phospholipids, while neutral lipids were relatively stable. The contents of monogalactosyl diglyceride, digalactosy diglyceride, sulfoquinovosyl diglyceride and phosphatidyl choline decreased notably.

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The purpose of this study is to look into applicability of Ultra-Violet (UV) to sterilizing the surface of sausage. At first, stenlizing effect of UV was examined in regard to the suspension of E. coli and B. subtilis spores. In the next, sterilizing effect on the surface of wiener sausage was examined by an UV sterilizing device which was made on an laboratory scale. (1) In the suspension of bacteria, irradiation time of UV required to destroy E. coli from the level of 10⁷ to 10⁰ was around 13 seconds for 2mW/cmcm², and around 2 seconds for 60mW/cmcm². In deStroying B. subtilis spores from 10⁶ to 10⁰, the time was around 120 seconds and 5 seconds each. (2) In the experiment by wiener sausage, UV-lamp with high intensity more than 40mW/cmcm², being irradiated for five seconds, sterilized bacteria adhered to the surface of sausage to the level of less than 5. This result was obtained in regard to E. coli (10⁵ per sausage) as well as B. subtilis spores (10⁴ per sausage). (3) Sterilizing effect at the edges of sausage was inferior to the surface of sausage. This fact was, we considered, caused by shadows at the edges made by ray of the lamp.

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Acetone extract of fresh radish root turned yellow when the extract was freeze-dried or concentrated in vacuum, but no change in color was observed with boiled radish root extract. The precursor of the yellow substance was fractionated and isolated using Amberlite IR-4B resin, neutral Aluminium oxide, DEAE-cellulose, and paper chromatography. The isolated compounds were identified with GC-MS analysis and 4-Methylthio-3-butenyl glucosinolate was found to be the main precursor of the yellow substance. For the formation of yellow substance from glucosinolate coexistance of unidentified compounds were required. These were separable from the glucosinolate fraction by paper chromatography. Some factors affecting the yellowing reaction were also investigated. In the model system which was composed with 4-methylthio-3-butenyl glucosinolate fraction, McIlvaine buffer, L-ascorbic acid solution and radish enzyme solution, optimum pH value and temperature for the yellowing reaction were 6.0 and 40°C, respectively. L-Ascorbic acid stimulated the formation of yellow substance. These characteristics of the reaction were the same as those of myrosinase. From these results, hydrolysis of the radish glucosinolate by myrosinase seemed to be the first step in the yellowing reaction of fresh radish root extract.

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To know the natural antioxidative substances, fractionation of antioxidants from cacao bean husk has been performed. (1) Antioxidants from cacao bean husk was effectively extracted with 1/50N sodium hydroxide solution and the extracted fraction was precipitated by the addition of acid or alcohol. Fractionated several precipitates had antioxidative activity on linoleic acid. (2) Antioxidative substance of the fraction were studied by paper chromatography. Amino acid, catechin, P-chumaric acid and chlorogenic acid has been demonStrated. Among detected polyphenols, catechin and chlorogenic acid had strong antioxidative activity.

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Antioxidative activity of pigment extracted from cacao bean husk and synergistic effect of pigment with citric acid, melanoidin and tocopherol were studied. (1) In the range of 100-800μg, pigment had antioxidative activity to linoleic acid. (2) Synergistic effect of pigment with melanoidin was recognized but those with citric acid and tocopherol were not observed. (3) In comparison of antioxidative activity of pigment with tocopherol to margarine, effect of pigment was weaker than that of tocopherol. (4) In application test of pigment and melanoidin to biscuit, oxidative stability of biscuit was highly improved.

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Sixty-five strains of fungi were cultured in the liquid medium containing mandarin orange peel as a carbon source, and eight of them were chosen as effective producers of pectic enzymes. Especially, Aspergillus niger 35-1 was the most active in hydrolyzing mandarin orgnge peel. Production of pectic enzymes in the liquid culture of Asp. niger 35-1 and their characteristics were examined. Mandarin orange peel was found to be a favorable carbon source for the strain 35-1. Polygalacturonase (PG) activity was observed in 7 days of culture in shaking and maximum enzyme activity of PG reached 11.7 units per m1 of the culture medium. The optimum pH and temperature for the action of PG of this strain upon pectic acid were 2.5 to 4.0 and 55°C, respectively.

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Intermediate moisture foods (I.M.F.) are made their shelf life longer by means of controlling water activity (Aw), pH and/or adding preservatives. Crystallized fruits that are used for confectioneries are required to have juicy and soft texture. However, the more they get juicy, the more they get molded because of their higher moisture content. In this work, improvement of the quality of crystallized fruit was attempted by controlling Aw with various composition of sugar that is main component of crystallized fruit. Aw value of the crystallized fruit markedly decreased when small molecular such as glucose or inverted sugar is used on boiling process of the fruit. Using of inverted sugar in place of glucose resulted in better product quality. The mold that grew on the crystallized fruit was identified as a kind of Penicillium sp., whose minimum Aw of growth was 0.799. The product whose Aw value was lower than 0.799 was obtained by using 50% of inverted sugar and 50% of sucrose for boiling syrup. I.M.F. technology was successfully applied to crystallized fruit, and the standard value of Aw was obtained which was in the range of 0.570-0.789 for guaranteeing the good quality and long shelf life.

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Nucleosil 5 NH² column was employed for a high pressure liquid chromatographic determination of sugars in fruit juices (23 samples), fruit drinks (63 samples) and carbonated drinks (21 samples). Among the fruit juices, SATUMA mandarin contained a large amount of sucrose, while its Content was little in grape juice. The specific sugar composition was not observed on the drinks whose juice content were low because of the influence of further addition of sugar compound. Consequently, both of sugar composition and its ratio in the samples were nearly constant, independently of a kind of the fruit used. Many carbonated drinks without addition of fruit juice were found to be supplemented with sucrose, showing twice of the content in drinks added with fruit juice.

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In processing both of buckwheat noodles and of Japanese noodles, no established method for evaluating any agents which improve the functional properties of noodle-dough has ever reported. In this respect, the applicability of 13 commercial vital glutens from various sources were investigated. The trial noodles made from a model mixed flour composed of wheat starch and the individual commercial glutens were submitted to organoleptical evaluation of the functional performance, and to the measurements by Brabender's instruments. The desirable consistency of the intermediate products was investigated in relation to the physical and chemical properties of glutents, and to the instrumental data of Farinogram and Extensogram for the model flour systems as well as to the characteristic phsical properties of the final dried products. For instance, the higher solubility of any gluten in 0.1 N acetic acid did not necessarily mean the better consistency in noodle processing. As a practical conclusion, the commercial glutens which were produced by the spray-drying method of the dispersion in ammonia medium were found to be the most applicable ones to the buck wheat noodle processing, with only one exception.

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