The influence of added proteins (gliadin and glutenin) on the farinograph parameters of dough was in vestigated with three kinds of wheat flours (hard wheat flour, soft wheat flour and durum wheat flour). By the addition of gliadin, similar changes in the quality were observed for all three wheat flours; an increase in protein content was accompanied by an increase in the maximum consistency concomitant with a decrease in the farinograph peak time and a marked decrease in the tolerance index., In the case of glutenin, on the other hand, the values of the tolerance index were reduced, and the farinograph peak time of durum wheat flour was extended by increasing protein content, although that of the other flours showed a similar tendency when gliadin was added. A synthetic flour dough consisting of starch and isolated gliadin or glutenin gave a similar farinograph pattern in any pairs of combination, indicating that the absence of either gliadin or glutenin resulted in the poor quality doughs. Microscopic examination of the gluten matrix of the synthetic flour dough containing either gliadin or glutenin did not reveal the presence of an extended network structure observed in natural wheat flour doughs. The durum wheat flour dough had a relatively large network structure of gluten matrix, and was of low farinograph absorption. However, it required a long time to form the network structure, which was stable as compared with those of the bread wheat. It is also suggested that the quantity of immobilized water in the doughs is controlled by gliadin in the gluten matrix, although the capacity of the immobilized water essentially depends on the characteristics of glutenin.

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Inorganic UF membranes (molecular weight cut-off (MWCO); 20000 and 60000-80000 daltons) and two types of dynamic UF membranes (a pre-coat type and a self-rejecting type) were applied to clarify Japanese pear juice. The inoganic UF membrane of MWCO 60000-80000 and the dynamic UF membrane which was pre-coated by depositing Zr colloids 80000 and the dynamic UF membrane which was pre-coated by depositing Zr colloids surface of a ceramic support were suitable for clarification of the juice. They provided not only both high rejection ability of pectin and flux but also the similar sugar and acid contents to the commercial clear juice treated with pectinase. Separation of suspended solids in the sample juice by centrifugation caused a decrease in flux of the permeateof the dynamic UF membrane. During the clarification by the membrane, pectinase treatment ofthe dynamic UF membrane. During the clarification by the membrane, pectinase treatment of the sample juice resulted in little change in the components, but gave higher permeate flux than withoutpectinase treatmen

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The comparison of volatile components in the peel oil of navel orange wascarried out to elucidate the difference of aroma quality between closely related species. The essential oils were prepared by simultaneous distillation-extraction, from four species of nave ls such as Washington (Citrus sinensis Osbeck Washington), Hukumotobeni (C. sinensis Osbeck cv. Hukumotobeni), Ohmishima (C. sinensis Osbeck cv. Ohmishima), Shiroyanagi (C. sinensis Osbeck cv. Shiroyanagi), which were harvested in Shikoku, Japan. Each oil was separated into hydrocarbon and oxygenated compound fractions through a silica gel column, and analyzed by acombined capillary gas chromatograph-mass spectrometer (GC/MS). Twelvecomponents in the hydrocarbon fraction of each peel oil were identified by GC/MS and Kovats Indices. Moreover, 68 components in Washington navel, 62 components in Hukumotobeni, 58 components in Ohmishima, 65 components in Shiroyanagi were identified as the oxygenated compounds. As these oxygenated fractions had the characteristic aroma of the peel oil, they were further separated into four fractions, and then examined by GC/MS and GC-sniffing. The character impact compound of navel orange aroma was not found, but it was suggested that floral, herbaceus and fruity components were important to navel orange aroma and their interaction affected mainly to the characteristic aroma of navel peel oil.

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Catechin fraction A (CF-A) containing (-)-epicatechin and (-)-epigallocatechin, fraction B (CF-B) containing (-)-epicatechin gallate and (-)-epigallocatechin gallate, CF-Aand CF-B mixture (CF-mix), and(-)-epigallocatechin gallate (EGCg) were prepared fromgreen tea by using the method of YAYABE et al., and the antibacterial activity of catechins onthe S. mutans was investigated. On the antibacterial effects to S. mutans, minimal inhibitoryconcentration (MIC) of CF-A, CF-B, CF-mix, and EGCg was 400-100, 100-50, 200-100, nd 100-50μg/ml, respectively. MIC of chlorohexidine gluconate solution was less than1.6ug/ml. On the sterilization effect, an addition of 20mg/ml of CF-B decreased the numberof S. mutans from 10⁷to 10² after 3min, while achlorohexidine gluconate solution showedabout 10 times higher sterilization activity. Although the antibacterial and sterilizationeffects of the CF-B were mild compared with those of chlorohexidine gluconate, it may beuseful as a natural antibacterial reagent for a dentifrice or a mouthwash liquid etc. due to itsreasonable antibacterial activity to S. mutans.

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This paper describes the properties and the degradation of spherosome in rice bran. The chemical components of rice bran spherosome were: diameters: 1-3μm; 1ipid content: 98.7%, and protein content: 1.3%. The ratio of neutral lipids, glycolipids and phospholipids were 98.6: 0.5: 0.9. Triacylglycerol (TG), steryglycoside, and phosphatidylcholine were the major lipid components in the above neutral liplids, glycolipids and phospholipids, respectively. When lipase, phospholipid acylhydrolase, phospholipase C and phospholipase D were added to rice bran spherosome, only phospholipase D degraded it through the enzymatic hydrolysis of phophatidylcholine of the spherosome membrane to phosphatidic acid. It was concluded through this study that at the initial stage phospholipase D reacted with the phospholipid membrane of spherosome to damage its structure, which then allowed TG to get out through the spherosome membrane. After that lipase decomposed TG to free fatty acids.

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Recently, chlorophyll (Chl)-containing fried foods and vegetable snacks have been widely consumed in Japan, because their green color provides consumers with a good image for health. It is well known that oxidative deterioration of fats and oils is greatly enhanced by light, especially in the presence of Chls. In this study, the oxidative deterioration of oils extracted from commercial fried foods containing Chls was investigated, and the effect of light irradiation on the deterioration of those foods was examined. The following experimental results were obtained; (1) Amarked deterioration was not observed in Chl-containing fried foods purchased from two big supermarkets within one or two months from the production date. (2) On leaving fried snacks after unsealing at room temperature under the dark for 2 weeks, autoxidation of their fatty components obviously proceeded. (3) When several vegetable snacks were irradiated by light (sun light or 15W fluorescent light) for 2 weeks, a remarkable increase of peroxide values was observed in Chl-containing vegetables (kidney beans and green peas).

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To obtain lipase high-producing microorganisms, 556 microorganisms isolated fromsoil and cacao beans were screened. One strain identified as Rhizopus oligosporus was found to produce extracellularly a large amount of lipase in the shaking culture. When cultivated at 30°C for 5 days in the medium containing 2% (v/v) olive oil, the strain produced 16.7U/ml of lipase.

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The kind and amount of hydroxycinnamic acids occurring in the roots of radish (Raphanus satiuus L.) cultivated in Japan were investigated. In the ethyl acetate extracts of roots prepared under the acidic condition, malic acid esters of p-coumaric acid and ferulic acid were identified as main hydroxycinnamic acids. In quantitative analysis, the esters which were partially purified by C₁₈ SEP-PAK cartridges were converted into liberated form by an alkaline-hydrolysis, and HPLC analysis was accomplished. In 13 varieties of radish, the amounts of p-coumaric acid and ferulic acid contained as malic acid ester were 1.26-8.58mg per kg and 0.24-1.12mg per kg, respectively.

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The flavor constituents of Pu er Cha, which was made from Chinese green tea by microbial-fermentation, were analyzed by GC and GC-MS. The ether extracts of the samples have characteristic moldy odor. The main flavor constituents of them were constructed from linalool and its oxides, aliphatic aldehydes (n-haxanal, E-2-pentenal, E-2, Z-4-heptadienal etc), and ionones and its oxidiging compounds (dihydroactinidiolide etc). These compounds seemed to be produced during manufacturing process such as solar drying and/or fermentation with microorganisms.

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Contents of tocopherols (α-, β-, γ-, and δ-Toc)in 14 kinds of green coffee beans, each ofwhich had its own brand name, their roasted beans, infusions of those beans, and 38 kinds of instant coffee were determined by high-performance liquid chromatography. In 14 kinds of green coffee beans, total Toc of 12 kinds of them were more than 10mg/100g, the maximum was 15.7mg/100g and the average was 11.9mg/100g. The contents of α-Toc were 2.3-4.5mg/100g and the average was 3.5mg/100g. The contents of β-Toc were 3.2-11.4mg/100g and the average was 8.4mg/100g. γ-Toc and δ-Toc were not found. Eighty-three to ninty-nine % (averge 94%) of total Toc, 79-100% (average 91%) of α-Toc and 84-100%(average 95%) of β-Toc were remained after roasting. The content of β-Toc in the coffee beans was higher than α-Toc whose ratio was 1:2-3 except one whose ratio was 1: 1.5. The content of total Toc in coffee infusion or instant coffee solution was O.007mg/100ml. From these fact it was concluded that only 0.4-1.8% of Toc was infused from the roasted coffee beans.

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The effects of sodium chloride (4-10%) and ethanol (8-12%) concentrations on ripening of salted sea urchin gonads were investigated. The viable cell count of salted gonads decreased to a level of below 10³ per g from 4.9×10⁴ of fresh gonads during 1 month of ripening and did not change during storage of 12 months. It was suggested that the changes in components of salted gonads during ripening may be attributable to enzymes of sea urchin gonads rather than to those of microorganisms. The salted gonads softened gradually with ripening. The pH of salted gonads was in the range of 6.0 to 6.5 throughout ripening. The changes in the firmness of salted gonads and pH were independent of sodium chloride and ethanol concentrations. The total and reducing sugars in the extracts increased with lowering of the concentrations of sodium chloride and ethanol added throughout ripening. The total and amino nitrogen contents in the extracts increased slowly during 12 months of ripening. The amount of volatile base nitrogen (VBN) in the extracts increased with lowering of the sodium chloride and ethanol concentrations. The VBN of good-tasting salted gonads was determined to be in the range of 20 to 50 mg/100g.

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New database system of information of chemical substances related to food processing was developed. The system function was designed and application softwares were developed. The host computer system was ACOS-850, and DATA-710^TM was used as DBMS (Database Management System). The outline of the database is as follows. It includes physical data, spectral data, biological data, production and shipment data and legal data of food additives, enzymes and microbial products. Text data are written in Japanese. The software program to exchange the data between this database and other ones which were controlled by IBM^TM system was also developed.

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Effect of low pressure was investigated on the preservation of avocado and papay a Fruits with a view of applying this technique to the storage of fruits by using a pract ical apparatus. Effects of a low partial pressure of oxygen at a low temperature were clearly de monstrated on the retardation of ripening, prevention of deterioration and decay compared w ith normal pressure storage at a low temperature. The maturity of papaya fruit stored at a low pressure and low temperature was dalayed by 3 weeks compared with the fruits kep t at a normal pressure and low temperature during 40 days storage, when the fruits used were immature at the time of harvest or prior to transportation. The firmness and the peel coloration of the papaya fruits could be kept in better condition during 40 days storage period by treatment with hot water dips, than those of the fruits not subjected to hot water dips.

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