Dielectrophoretic effects on demulsifications of water in oil (W/O), glycerin in oil (G/W) and starch suspension in oil (S/O) or saponified material in oil (Sp/O) prepared by edible oils were investigated. Demulsification of W/O could be done by about 4kV and 100min running and that of G/O was done by about 6kV and 150min running. A critical removal ratio of water and glycerin from W/O and G/O emulsions were about 0.1% by a trial dielectrophoretic apparatus. Their figures were similar to that of kerosene emulsion. Defecations of S/O and Sp/0 were difficult with the test dielectrophoretic apparatus.

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Differential scanning calorimetry, dynamic viscoelastic and breaking stress measurement were carried out for gellan gum gels containing NH₄I, NH₄Cl, NH₄Br or NH₄F. Breaking stress andstorage shear modulus G' of gellan gum gels containing NH₄I, NH₄Cl and NH4Br increased in proportion to an ammonium salt (0-50mM) concentration. But in the case of gels containing fluoride ions, these increases were only observed for samples with low salt concentration and after the sharp drop of these values, then these increased again. The exothermic peak temperatures accompanying sol-to-gel transitions shifted to higher temperatures with increasing salt concentration. This has been attributed to the shielding of the electrostatic repulsion of carboxyl groups in gellan gum molecules by ammonium ions. In both thermal and rheological properties, gels containing fluoride ions showed different behaviors from those containing iodide, bromide or chloride ions.

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Effects of heating a soy protein solution prior to freeze-drying and of protein conc., pH, etc. of the protein paste during cold stosage on gel formation properties were investigated. Soy protein isolate heated at above 100°C formed a gel during the 5°C-storage for 3days. The cold-gel showed 80% jelly strength and 150% strain of a heat-induced gel, in the texture. In soy protein, 7S globulin was mainly related to the gel formation. The minimum protein conc. necessary for the formation of a gel was 12% and the strain of cold-gel increased as pH increased. The gel obtained during the cold storage was apparently distinguishable from ordinary heat-induced gels and freeze-induced gels on its viscoelasticity.

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Effect of heating on the molecular structure of soy protein was investigated. In ultracentrifugal analysis, 7S and 11S components retained after heating at below 100°C, while they disappeared after heating at 140°C. In DSC analysis, after heating at above 100°C endothermic peaks of 7S and 11S components disappeared. In solubilization tests with urea and 2-mercaptoethanol, the maximum solubility was observed after heating at 100°C, indicating that binding capacities of hydrogen bond, hydrophobic interaction and disulfide bond, as well as the SH contents in the protein decreased as the heating temperature increased. In amylography soy protein heated at above 100°C showed a typical viscosity pattern in a swelling state. Fluorescent intensity and the intrinsic viscosity increased in accordance with an increase in heating temperature and showed maxima at 100°C heating. These observations suggest that the soy protein molecular structure after heating at 100°C would be in a highly unfolded state and become susceptible to intermolecular interaction.

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γ-Ray irradiation of fresh onion is useful method to prevent sprouting during storage. WHO/FAO have approved of 0.15 kGy irradiation to fresh onion for this purpose. Aiming at the wholesome-ness of food irradiation, we tried to compare the aroma constituents of irradiated onion during storage. Irradiated onions (0.2, 5.0kGy) were stored for 3 months and their aroma characters were assayed at regular intervals by head space vapor analysis with a thermal desorption cold trap (TCT) injection system. The chemical structures of twenty two compounds were identified or estimated. The gas chromatograms (GC) obtained from the onions irradiated at a dose of 0.2kGy were almost the same as those of non-irradiated onion during all the stages of 3months storage. The onions irradiated at a dose of 5.0kGy showed higher contents of disulfides and trisulfide on their GC. The similarities among GC patterns obtained from all these samples were calculated using 44 peaks strength commonly appearing on each GCs as respective variables for mathematical treatment. The result showed that GC patterns of 0.2kGy irradiated samples were almost similar to those of non-irradiated ones quantitatively. However, similarities between 0.2kGy and 0.5kGy irradiated samples were lower than those between non- and 0.2kGy irradiated onions. These results suggest that under the permitted irradiation, fresh onion does not show any changes in the aroma constituents which are the most unstable flavor components in onion.

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Minimum inhibitory concentrations of organic acids against 15 strains of bacteria, 6 strains of yeasts, and 2 strains of molds were determined in the media with diffesent pH ranged from 4.0 to 7.0. Formic, acetic, and propionic acids showed almost similas activities of growth inhibition against most strains of microorganisms except that formic acid showed stronger activities to lactic acid bacteria and weak activities to fungi than other two acids. The activities of sorbic acid were different from those of other fatty acids such as acetic and propionic acids, and were stronger against yeasts and molds than to bacteria. The activities of lactic acid (D and L form) were most characteristic. It inhibited growth of all strains of lactic acid bacteria in any ranges of pH. On the contrary, there were no acitivities by lactic acid against fungi. Malic, tastaric, gluconic and citric acids showed rather weak acitivities to any kinds of microorganisms. Citric acid only showed moderate activities against some strains of lactic acid bacteria. Adipic acid showed very strong activity in lower pH ranges and no activities in the pH ranges above pH 6.0. Effect of pH on the antimicrobial activities of adipic acid was extensively large compased with those of other acids. And adipic acid showed almost no activity to fungi. These sesults elucidated that each organic acid had inherent antimicrobial activity individually.

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The effect of ozone exposure (concentration: 0, 0.03 and 0.1ppm) during cultivation of Nameko mushroom (Pholiota nameko) was investigated on the fatty acid composition of fruit bodies i.e. pileus, stipe and whole fruit body. On the ozone treatment, an increase was observed on the palmitoleic acid content and oleic acid/linoleic acid ratio in pileus, stipe and whole fruit body. Also an increase was observed on oleic acid content in pileus and whole fruit body. On the other hand, a decrease was observed on the linoleic acid content and polyunsaturated fatty acid/saturated fatty acid ratio in pileus, stipe and whole fruit body. The pileus, as compared with the stipe, was highly affected by ozone exposure.

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The effect of ozone exposure (concentration: 0, 0.03, 0.1 and 0.3ppm) during cultivation of Oyster mushroom (Pleurotus ostreatus)was investigated on the weight and chemical composition (water, protein, lipid, carbohydrate and ash as major constituents; Ca, Fe, Na, K and Zn as minerals; and thiamin, riboflavin and ascorbic acid as vitamins) on dry matter basis of fruit bodies i.e;, pileus, stipes and the whole. On the ozone treatment, an increase was observed on the weight of the whole bodies. An increase was also observed on the water content, and protein, Ca, K, Zn, riboflavin and ascorbic acid contents in the whole bodies. An increase was observed on the water content, protein, Na, K, Zn and vitamin contents except thiamin in the pileus and in the water content, Ca, K and ascorbic acid contents in the sipes. On the other hand, a decrease was observed in carbohydrate, Fe and thiamin contents in the pileus, in thiamin content in the stipes, and in Fe and thiamin contents in the whole bodies.

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The water extract fraction of wasabi (Eutrema wasabi Maxim.) markedly suppressed the growth of MKN-28 human stomach cancer cells. When MKN-28 cells were cultured with more than 40μl/ml of the water extract of wasabi, they were underwent morphological alteration with frequent cell death. The substances that suppressed the growth of MKN-28 cells were existed in the fraction consisting of components with molecular weights under 5000. The growth-inhibiting effect on MKN-28 cells was unaffected by treatment at 90°C for 10min. Shinigrin and isothiocyanates which are main components of wasabi had no growth-inhibiting effect.

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Seventy-five kinds of desserts were collected in the market and were prepared by addition of water or milk. The sugar content (monosaccharides and disaccharides) were estimated. The table of sugar composition in the desserts was prepared. The table includes brand names because of variation of sugar contents between makers and/ or kinds of dessert. Sucrose content was the highest in any dessert (29 samples contained above 10g of sucrose), while fructose was scarcely detected other than sarcocarp or pectin added liquid products. Daily sugar intake in 70 college men living in Osaka was estimated. That was 5.9±4.0g (M±SD) of fructose, 6.1±3.7g glucose, 26.7±1.0g of sucrose, 0.6±0.5g of maltose and 7.1±5.0g of lactose from snacks including commercial desserts. And that was 3.3 ±3.5g of fructose, 4.9±7.3g of glucose, 14.1±7.7g of sucrose, 0.9±0.7g of maltose and 3.7±3.3g of lactose in 70 college women living in Osaka.

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Chum salmon (Oncorhynchus keta) surimi has good cofor, flavor and taste characteristics, butis difficult to gelatinize hard without heating. This paper shows that chum salmon surimi can be gelatinized by fermentation with lacti cacd bacteria at 15 or 20°C for 5 to 11 days. Lactobacillus plantarum JCM ll49, Leucomstoc mesenteroides JCM 6124, Pediococcus acidilactici JCM 5885, and Lactococcus lactis subsp. cremoris IFO 3427 were used for fermentation. The gelatinized surimi was of good quality in texture, flavor and taste.

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Asystematic method for the fractionation and purification of antitumor polysaccharide fractions from the mycelium of liquid-cultured Grifola Frondosa was established. Twenty-three polysaccha- ride fractions were obtained. FI₀-a-α, FI₀-a-β, FA-1 and FA-2-b-α in water-soluble fractions showed better antitumor activity against Sarcoma 180/mice, FIII-1-a, FIII-1-b, FIII-2-a, FIII-2-b and FIII-2-c in water-insoluble fractions markedly inhibited the growth of Sarcoma l80/mice. In addition, administration of each of FI₀-a, FIII-1-a, FIII-1-b, FIII-1-c, FIII-2-a, FIII-2-b, FIII-2-c to mice could cause an evident increase in antigenic C3 release from macrophages. These results suggest that active polysaccharide fractions, which were considered to be heteroglycan or heteroglycan-protein complexes, can depress or reduce tumor growth by activating the immune system as a biological response modifier (BRM).

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Twenty-three chemically-modified polysaccharides, including five polyaldehyde-, ten polyalcohol-, four formylated-polysaccharides and four formolysis products of polysaccharides, were prepared from nine mycelial polysaccharides of Grifola frondosa. Although two of the original polysaccharides (FA-3, FA-2-b-β and FII-b) had no activity, their polyaldehyde-, polyol-, formylated-, and formolysis derivatives showed significant activity. Polyaldehyde-, and polyol-polysaccharides prepared from a polysaccharide (FI₀-a-β) with low antitumor activity showed activity higher than the original polysaccharide. Polyaldehyde- and polyol-polysaccharides prepared from polysaccharides (FIII-1-b and FIII-2-b) with relatively high activity also showed antitumor activity higher than the original polysaccharide. The formolysis product of FIII-1-insoluble with relatively high activity did not few increase in antitumor activity (Sarcoma 180/mice) compared with the original polysaccharide, but also show the complement C3 activation on macrophages.

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