Dynamic ultrafiltration membranes could be formed by various concentrations of ovalbumin solutions, fed over the ceramic support of which pore size was 0.05μm. It is found that rejections were almost 95%, steady flux of this membrane was depended on the ovalbumin concentration, and the optimum conditions of membrane formation were 140cm sec^-1 and O.5MPa at 25°C. The flux of the membrane made under the optimum conditions reached minimum near the isoelectric point of ovalbumin and extremely increased with decreasing pH. It is supposed that the performance of ovalubmin membrane was strongly affected by the nature of ovalubmin. These membranes could easily be removed by washing with NaClO.

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Wheat starch suspensions isolated from six flour mill streams milled on a Buhler laboratory mill were separated into upper layer (starch tailings) and lower layer (prime starch) fractions by centrifugation, and their qualitative and quantitative characteristics were compared between Australian Standard White Wheat (ASW) and Japanese domestic wheats. Large amounts of starch tailings were isolated both for the latter part of break and reduction flour mill streams. Starch tailings and prime starch differed in their amylose contents as analyzed by an amperometric iodine titration method. Prime starch isolated from ASW characterized in its most stable iodine-binding capacity for the changes of temperatures during measurement as well as its lowest amylose content. Critical difference was observed for the digestibilities on sulfuric acid between starch tailings and prime starch. ASW starch showed intermediate digestibility as compared with that of Japanese domestic wheat starches. There was little difference in the contents of phosphorus for five different kinds of wheat starches examined, although starch tailings showed somewhat higher values.

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To clarify the chilling injury mechanism of apples the molecular species of phosphatidyl-choline in apples cv. Fuji were examined by means of argentation thin layer and gas-liquid chromatographies. The results obtained were as follows: 1) In the case of a sample just after harvest, the bands of phosphatidylcholine with 100% or near 100% of unsaturated fatty acid composition were found by the above50%. The above facts seem to be one of the reasons why chilling injury does not occur in the apples cv. Fuji. 2) Furthermore, in the case of samples after 5, 7 and 9 months storage at 0°C, the bands with over 80% of unsaturated fatty acidcomposition were detected. This fact seems to be one of the reasons why the apples cv. Fuji do not show chilling injury and therefore are suitable for cold storage. 3) The kinds of molecular species of phosphatidylcholine in the apples cv. Fuji decreased after cold storage for seven months.

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Screening for antioxidative activity of 117 parts consisted of edible plants (107kinds) were performed on their ethanol extract. About half of them showed some influence on oxidative stability of methyl linoleate. Especially 26 species of them seemed to have rather strong antioxidative activity. Selected 14 samples of the active plants were further examined on the activities of their ether, ethanol and water extracts to linoleic acid, respectively, in emulsion system. The active components of the each sample showed individual and different behaviors to the solvent extractions. On the other hand, the contents of α-, β-, γ- and δ-tocopherol were determined by HPLC to clarify the active component of the antioxidative effects. Tocopherol seemed to contribute some role in the antioxidant activities of the several plants, but most of them suggested the presence of other effective substances.

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A mixture of tannic acid and gelatin was designed for use as a chewing gum base. The mixture was a chewable material like chewing gum on the market. The characterist ics of the mixture were found as follows. (1) The mixture formed chewing gum by applying repeating press and folding regularly in water. (2) During the above operation, the mixture absorbed water at first, some parts of tannic acid and gelatin were released from the mixture and the remains formed chewing gum. (3) When the ratio of tannic acid to gelatin was lower than O.2, the mixture did not form chewing gum but melted in water. When the ratio was near O.5, the mixture formed bubble gum. (4) The mixture containing much wat er was soft, but formed a tight chewing gum after the operation. (5) The mixture made from acid-processed gelatin formed chewing gum in a wider range of pH than the mixtur e made from alkali-processed gelatin.

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Stevioside (β-D-glucosylester of 13-O-β-sophorosyl steviol) was hydrolyzed by the enzyme in raw soy sauce. The hydrolyzate was identified as rubusoside (β-D-glucosyl ester of 13-O-B-D-glucosyl steviol) by its physical properties. The sweetness of rubusoside was about 0.3 times of stevioside on the 0.1% (w/v) concentration of aqueous solution.

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Browning products were prepared between glucosamine and one of the following compounds; amino acids (6 kinds), organic acids (4 kinds), sugars (5 kinds) by incubation at 37°C for 30 days or heating at 100°C for 30 and 60min. The antioxidative activity, reducing power, residual aminosugar, degree of browning and pH of these browning product solutions were measured. These browning products showed stronger antioxidative activities than glucosamine alone. The strongest antioxidative activities were observed, in the reaction with L-leucine, D-glucose, or succinic acid by incubation at 37°C for 30 days, and with L-leucine, D-glucose, or L-ascorbic acid by heating at 100°C for 60 min. Stronger antioxidative activity and higher browning degree were derived from the longer incubation time and the higher temperature employed in this study.

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This paper describes the seasonal changes in pectin content and pectinmethyleste rase (PE) and polygalacturonase (PG) activities in two cultivars of kiwifruits, 'Kory oku' and 'Hayward'. The main purpose of the study was to investigate the seasonal change s in pectin content on the basis of PE and PG activities and their properties. PE showed hig hest activity in September in both cultivars and decreased to about half in November. On the other hand, PG showed almost constant activities in both cultivars. Total pectin (TP) content was highest in September for 'Koryoku' and in October for'Hayward', whereas water soluble pectin (WSP) was lowest in October for both cultivars.

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A process controller for automatic operation of food steamer was developed. It consisted of a microcomputer, interfaces, and software including subroutine programs. Performance of the controller was tested by the use of a Kamaboko (a fish meat gel) steamer made on experimental basis. Almost all the temperature measured in the steam box were found within the range of 88-92°C, when the controller was set to maintain at 90°C by means of the fuel gas control of boiler. The results demonstrated that the controller developed was useful in practice.

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