Analysis of physical properties was performed on egg white gels modified by incorporation of powdered chitin filler into the sol, followed by thermal gelation. The physical properties of the gels changed with the protein concentration, where the values of mechanical parameters corresponding to hardness and fracturability increased and those corresponding to elasticity decreased with increasing protein concentration. The values of mechanical parameters which relate to hardness of the egg white gel were raised by the addition of powdered chitin, which resembles the influence caused by an increase of protein concentration. Both size and concentration of the chitin filler had changeable influences on the gel properties of egg white. A combination of size and concentration of the fller induced an increase of elasticity and fracturability of the gel, which differed from the effects by the protein concentration. Thus, there may be flexibility for setting the combination of size and concentration of the powdered chitin filler in modification and/or control of the physical properties of egg white gels.

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Although it is known that the physical properties of whip cream vary with tempering, few investigations reffer to the whipping properties. The effects of tempering condition on the viscosity and whipping properties of sterilized imitation whip cream were investigated. The whip cream was cooled to the required temperatures (Tr) of 5, 10, 20, 30, and 60°C after sterilization, and stored at 5°C for a week. It was then warmed to tempering temperatures (Tt) of 25, 35, 45, and 60°C, and stored again at 5°C. The viscosity and whipping properties were strongly influenced by (Tt) than (Tr). After tempering, the whipping time and the overrun decreased, while the firmness of the whipped cream and the viscosity increased in a (Tt) range from 25 to 45°C; however, the viscosity and whipping properties were equivalent to those without tempering above 45°C. The free fat content in the whipped cream increased after tempering from 25 to 45°C and it was equivalent to that without tempering above 45°C. Consequently, it was proved that changes in the whipping properties after tempering were caused by an increase of the free fat content in the whipped cream. The whipping properties also depended on the cooling rate after tempering. And the procedures, where the whip cream was first treated at (Tt) of 25, 35, 45, and 60°C and then again at 60°C, canceled out the influence of the first tempering on the whipping properties.

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A combined process of freeze concentration and pressurization produced gels from raw cow's milk without using gelling agents. Gelation was observed when milk was freezeconcentrated at solid concentrations of 25% or higher. Urea and EDTA inhibited gelation, however, proper concentrations of sucrose was favorable for gelation. Pressurization resulted in formation of casein particles of the size between casein micelle and submicelle, which contributed to pressure-induced gelation. Sucrose was considered to inhibit aggregation of casein particles.

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Maltooligosaccharides were found in extracts of cooked rice. The amounts of sugars differed among sample cultivars. For example, the extract of "Koshihikari" contained much sugars than that of "Nipponbare". Soaking condition during cooking also affected the amounts of sugars. The longer time in soaking or the higher temperature at soaking caused larger amounts of the sugars.

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Mixtures of two compounds and volatiles in the Citrus peels were analyzed by six semiconductor gas sensors. From the result of mixed compounds, responses of semiconductor gas sensors were affected by vapor pressures of individual compounds. It was found that sensor responses as well as vapor pressures changed by the solubility and the ratio of the concentration of compounds dissolved in the solutions. On the other hand, Citrus sudachi, Citrus limone, Citrus iyo, two Citrus sinensis, and two Pummelos were used for the sensor analysis as the samples. Factor analysis of the response patterns of six gas sensors was conducted and then factor l and factor 2 scores were plotted on a two dimensional diagram. The factor scores of Citrus sudachi and Citrus limone were located in the similar area and formed individual groups. However, the other orange families except one Pummelo were dispersed on the close area of the diagram. One Pummelo was dispersed widely on the diagram. The discriminant analysis of response data of semiconductor gas sensors for Citrus peels distinguished more than 70% of probability as the response of the correct fruit. We tried to explain the distribution of the factor scores of Citrus fruits by sensor responses to model mixtures of 5 compounds (limonene, β-pinene, γ-terpinene, myrcene, and linalool) found in individual fruits as the main components. However, it could not be explained by the small number of compounds well because of the high similarity of sensor responses among limonene, γ-terpinene and myrcene.

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Ice cream having characteristic texture is produced by freezing a mix in an o/w emulsified state by a freezer. We have in vestigated the effect of drawing temperature at the freezer and overrun on de-emulsified fat. Ice cream consisting of vegetable fat 9.0%, M.S.N.F. 9.5% and total solids 38.0% was prepared by freezing the mix in a CREPACO continuous freezer. Conditions were varied as follows. The drawing temperature at the freeze was -3.5°C, -4.5°C or -5.5°C, the overrun was 40%, 70%, 100% or 130%, and the mix flow rate was 65l/h. The particle size distribution of the fat globules was measured by a Laser diffraction particle size analyzer. The fat de-emulsification rate was determined by the difference of the particle size distribution of the fat globules that were measured in ice cream mix and ice cream solution prepared by diluting ice cream at 5°C-10°C with 5 volumes of deionized water. Melting resistance wasexamined by the meltdown method. The fat de-emulsification rate increased in proportion to decreased drawing temperature, and the melting resistance improved. The fat de-emulsification rate increased in proportion to higher overrun, and the milting resistance improved. Dryness of ice cream increased in proportion to decreased drawing temperature and higher overrun. The particle size distribution of fat globules changed in proportion to the increased fat de-emulsification rate; fat globules of below 1.2μm decreased and the distribution of globules of from 3 to 4μm and 8 to 15/μm was unusually increased.

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Thermal gel-formation of air-blown flying fish muscle actomyosin sol was investigated under various conditions. The air-blowing treatment caused a protein concentration at the air-sol interface resulting in the thermal gelstrength reinforcement of the actomyosin sol. The moisture content-thermal gel-strength curve of the air-blown actomyosin sol gave a multilayer-type relationship. The effect of the air-blowing was higher at alkaline pH than at acidic pH, and for a high ionic strength above 0.4 M NaCl. The effect indicated that the thermal gel-strength increased proportionally to the 1.5 power of actomyosin concentration. The airblowing effect on gel-strength reinforcement was discussed in connection with interfacial denaturation.

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Effects of gamma-irradiation on lipid content of potatoes (cv. Dejima) were studied in relation to anatomy. The fatty acid contents of total lipids and phospholipids (μmoles FA/100g fresh wt.) varied with in tuber. In the central region of irradiated tuber, the fatty acid amounts in total- and phospholipids 3 days after irradiation were lower than those in unirradiated tubers. However, in both apical and basal regions the fatty acid amounts of irradiated tubers were higher than that of unirradiated tubers 3 days after irradiation. After 28 day storage, fatty acids in total and lipid in phospholipid were higher in all the region of irradiated tubers as compared with unirradiated ones. A significant increase of linolenic acid in glycolipid fraction was observed in irradiated tubers irrespective to sampling region.

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The possibility of application of starch hydrolysate was studied to improve the storage stability and physical property of low calorie sweetener composition including aspartame for yogurt. The effect of starch hydrolysate on the storage stability was determined by the quick accelerated storage test. Codrying of aspartame with starch hydrolysate was tested to improve the solubility of aspartame based on factorial experimental design. Application of starch hydrolysate with low dextrose equivalent (DE) and tertiary calcium phosphate improved the storage stability of low calorie sweetener using aspartame. Starch hydrolysate with the lower content of monosaccharide and disaccharide had excellent improvement effect on storagestability of this newly developed sweetener compound. The optimum spray drying condition which satisfied good solubility and bulkiness was established. The reason why the codrying of aspartame with starch hydrolysate improved the solubility of aspartame was discussed. Codried compound of aspartame and starch hydrolysate, prepared according to optimum spray drying condition, showed ag ood solubility and anappropriate bulk density. And this powder blended low calorie sweetener composition with fruit powder has undergone no significant deterioration after 2 years ambient storage.

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