This study was carried out on coagulation and curd formation of combined milk consisting of soymilk and bovine milk by the action of calf rennet. The coagulation time of combined milk by rennet delayed with higher ratios of soymilk to skim milk. The suitable coagulation time to form curd could be obtained by the adjustment of calcium chloride concentration in combined milk by the addition of calcium chloride solution to skim milk. Lactic fermentation also accelerated the coagulation of combined milk by rennet. The curd was prepared from combined milk (soymilk:bovine milk=1:1) containing 5mM of added calcium chloride by rennet action together with lactic fermentation. The yield of curd and solid in curd were 20.7% and 68.7%, respectively. Hardness, shear stress, gumminess, chewiness etc. of the curd were lower than those of soymilk curd and combined milk curd prepared by lactic fermentation treatment only. Scanning electron microscopic observation showed the curd had partially formed coagulates, aggregates of coagulates and large empty voids. In 3 week's curd ripened with Penicillium caseicolum, water soluble nitrogen ratio was approximately 40% and free glutamic acid content reached to 199mg/100g. The ripened curd had good umami taste and palatable texture but showed off-flavor with soapy and tallowy flavors.

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Effects of dry-heated egg white on Chinese type noodle were evaluated by rheological properties and sensory tests. The surface and cross-sectional structures of the noodles were also analyzed using a scanning electron microscope. The rheological properties and sensory evaluation showed that the dryheated egg white significantly improved Chinese type noodle on chewing texture, elasticity, stickiness and sensation on the palate. From the electron microscope observations, this improvement of the Chinese type noodle was considered to be caused by finer network structures constituted of wheat proteins and dry-heated egg white proteins.

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We prospected the antidotes from natural oriental drugs for botulinum neurotoxin type A. The crude extracts of Galla Rhois and Geranii Herba showed a potent antidote activity for botulinum neurotoxin type A. The antidote titer of the crude extracts of black tea was higher than those of Galla Rhois and Geranii Herba. No antidote activity was detected in the crude extracts of the followings: Gambir, Rosae Multiflorae Fructus, Scutellariae Radix, Coptidis Rhizoma, Sophorae Flos, Puerariae Radix, Houttuyniae Herba, Swertiae Herba, Galla Halepensis. Although both Galla Rhois and Galla Halepensis are gall-apples and contain tannin as the main component, Galla Rhois showed the potent antidote activity while Galla Halepensis did not.

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Wheat bran was hydrolyzed in subcritical water to increase the soluble dietary fiber (SDF). The SDF contents in wheat bran (WB) and subcritical water-treated wheat bran (SC-WB) were 10.4 and 23.2%, respectively, showing that SC-WB had about 2-fold higher SDF content than WB. Rats were fed a high-cholesterol (control) diet, or a control diet supplemented with WB (WB diet) or SC-WB (SC-WB diet) at 5% for 4 weeks. There were no significant differences in the concentrations of serum total cholesterol, HDL-cholesterol, and phospholipid among three groups. Although there was no significant difference between WB and SC-WB, both WB and SC-WB significantly prevented the elevation of serum triacylglycerol concentration and weight of mesenteric adipose (p<0.05). These results suggested that subcritical water treatment cause the increase of water soluble dietary fiber without the significant elevation of physiological activities for lipid metabolism.

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The Japan Agricultural Standard (JAS) revised in 2001 requires correct indication of species and origin of marine products. PCR-based DNA analysis have been focused on species identification in various marine products. We established methods for identifying three Perciforms species, Japanese sea bass Lateolabrax japonicus, Chinese sea bass Lateolabrax sp. and Nile perch Lates niloticus, by PCR-restriction fragment length polymorphism (RFLP) analysis and multiplex-PCR using species-specific primers. In PCR-RFLP, 377-bp long DNA fragments of the mitochondrial cytochrome b gene were amplified and cleaved by combination of two restriction enzymes Ssp I and Hha I or Ssp I and Mse I, indicating species-specific restriction fragment patterns for these species. In addition, species-specific primer sets were also designed by based on unique nucleotide substitution in each species, which showed different size of PCR-products among these species.

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In wasabi (Wasabia japonica, Japanese domestic horseradish), 6-methylsulfinylhexyl isothiocyanate (6-MSITC), one of its components, has been found to have activities to inhibit metastasis of cancer, to induce phase II enzymes, and to inhibit platelet aggregation. To establish a guideline for effective intake of 6-MSITC from daily diet, we have analyzed the 6-MSITC content in various species of wasabi and processed wasabi products.
The 6-MSITC content in different parts of five species of wasabi was analyzed. The result showed that in all species analyzed the 6-MSITC content was the highest in rhizome and then in the order of root, stem and leaf. Among the five species tested, the 6-MSITC content in rhizome was the highest in "Mitsuki", a high yield species. In Horseradish, however, the 6-MSITC content was below one-tenth of that in wasabi rhizomes. Furthermore, the 6-MSITC content in 25 types of processed wasabi products was analyzed. The result showed that there were great differences among manufacturers and types of products. The 6-MSITC content in processed wasabi products were related to the percentage of wasabi rhizome in the material. In conclusion, for effective intake of 6-MSITC from daily diet, it is most desirable to take the rhizome part of wasabi or choose processed wasabi products with a high percentage of rhizomes of wasabi.

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For the investigation of non-destructive measurement of fruit firmness, 6 cultivars of apple fruit were stored at 20°C after harvest. Every week, using 5-10 fruits, the frequency of second resonance of individual fruit were measured by a Laser Doppler Vibrometer (LDV) non-destructively, and the elastic indexes were calculated with the second resonance and fresh weight. Thereafter, the flesh firmness was measured by ordinary destructive method with the Magnes-Taylor fruit firmness tester. From the correlation coefficient between the elastic indexes and the firmness, the possibility to measure the flesh firmness of 6 apple cultivars by LDV method was evaluated. As the result, in 'Natsumidori', 'Iwai', 'Tsugaru' and 'Starking Delicious', the correlation coefficients were over 0.89, a practical possibility of this method was suggested. In 'Fuji' and 'Golden Delicious', however, the correlation coefficients were lower than 0.73, and 0.66, respectively. In these two cultivars, further analysis on this method are proceeding for the practical application.

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Actinidin, a cysteine protease in the fruit of Actinidia species, affects taste, allergenic properties and characteristics for processing the fruit. The actinidin concentration and the protease activity in the fruit juice of 12 Actinidia cultivars/selections were determined by quantitative sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a spectrophotometric assay using L-pyroglutamyl-L-phenylalanyl-L-leucine-p-nitroanilide as a substrate. In 'Sanuki gold' and 'Ananasnaya', both actinidin concentration and protease activity in the juice were much higher than those of 'Hayward', the most common cultivar of kiwi fruit. In contrast to these cultivars, both actinidin concentration and protease activity in 'First emperor', 'Tear drop' and 'Kosen' fruit juice were significantly lower than those of 'Hayward'. Specific activity of actinidin in A. arguta fruit was much higher than that in A. deliciosa or A. chinensis fruit.

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A method for estimating the remaining days of validity (RDV) during storage of fresh fish was proposed. This method is based on the K value which shows good correlation with "ikinoyosa", the freshness in the initial stage of storage. The proposed method can benefit to consumer side from the view point that consumers can judge RDV upon purchasing fresh fish. Consumers are thus able to confirm the safety of sashimi.

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