The effects of mixing rates (60, 150, 250, 350rpm) and the cooking times (15, 25, 35, 45min) on the texture of Gomatofu (sesame tofu) prepared from Kudzu and sesame milk were studied by using a rheometer (compression test), scanning electron microscope (SEM) and sensory tests (ranking and scoring methods). The hardness and gumminess of the sample cooked for 25min decreased up to 25 min and turned to increase over 25min of cooking increased with cooking time similar to the results obtained from penetration test in our previous paper. Adhesiveness depended heavily on the mixing rate in the penetrating test, but did lesser extent in the compression test. The sample of 250rpm for 25min was evaluated to have the best palatability but the samples of 60rpm for 15min and 350rpm for 45min had the worst texture organoleptically. SEM observation revealed that the sample of 250rpm for 25min had a uniform network structure and that the oil droplets got together and became larger in the sample of 350rpm 45min. Good positive correlation was obtained between texture measurement and sensory test in most of the samples. It was shown that smooth mouthfeel was the most important factor for the palatability of Gomatofu.

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Hardness of the reconstituted skim milk gel, prepared by adding glucono-δ-lactone (GDL), was measured in the presence of hypothiocyanite ion (OSCN^-) or hydrogen peroxide (H₂O₂) with a rheometer (Rheoner, Yamaden Inc., Japan). Both OSCN^- and H₂O₂ decreased the hardness of the gel, and the decrease in hardness was more significant by the addition of OSCN^-. The amount of sulfhydryls in reconstituted skim milk or β-lactoglobulin solutions was decreased by the addition of OSCN^- or H₂O₂, and OSCN^- was more effective on decreasing sulfhydryls. The hardness of the acid milk gel was proved to depend on the amount of sulfhydryls, in case that the other conditions were same. This study showed that the decrease in the hardness of the reconstituted skim milk gel was resulted from the decrease of sulfhydryls in milk proteins in the presence of OSCN^- or H₂O₂ which inhibited intermolecular S-S formation required for gel formation.

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The increase in industrial waste is one of the serious social problems. In this respect, we have searched for any useful materials from wastewater in cleaning of black sesame seed, one of food industrial wastes. In this paper, we describe the isolation, the structural elucidation and the antioxidative activity of four lignans, compounds 1-4, from the wastewater and on HPLC analysis of water extracts of black sesame seed coat and white sesame seed coat. Compounds 1-4 were isolated by column chromatography and preparative HPLC. On the basis of spectroscopic evidence, compounds 1-4 were respectively identified as pinoresinol, larisiresinol, hydroxymatairesinol, allohydroxymatairesinol. Compounds 2, 3, 4 have not been detected in sesame seed. On antioxidative activity by the thiocyanate method with AAPH, compounds 1-4 showed the weaker activities than BHT. On the DPPH radical-scavenging activities by a colorimetric method, compound 3 was as effective as α-tocopherol, and compound 4 showed the stronger activity than α-tocopherol. By HPLC analysis, it was ascertained that compounds 1-4 were not artifacts but were originally present in black sesame seed coat, in addition, it was proved that the content of compounds 1 and 2 in black sesame seed coat was four times more than that in white sesame seed coat.

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We found that the addition of glycosylhesperidin into orange juice solubilized hesperidin and prevented hesperidin crystal formation. We tried to use glycosylhesperidin as a hesperidin solbilizer in orange juice beverage which contain orange juice 30, 50 and 100%. When the orange juice beverage was produced, glycosylhesperidin (0.017-0.086%) was added. After 1 month, the amounts of hesperidin in supernatant and in precipitate were measured. It was found that 80-90% of the total hesperidin in the beverage were solubilized by adding the same amount of glycosylhesperidin as that of hesperidin originally in the beverage, and that the hesperidin precipitate disappeared visually. The mean size of hesperidin crystals in orange juice beverage with glycosylhesperidin (0.086%) was 7μm, whereas that of the beverage without glycosylhesperidin was 15 μm. From these results, glycosylhesperidin has two effects, solubilization of hesperidin and prevention of crystal formation. And then we studied the mechanism of these two effects of glycosylhesperidin by measuring the amount of glycosylhesperidin in the precipitate and the difference absorption spectra. It was suspected that glucosylhesperidin molecules formed a complex with hesperidin molecules.

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We evaluated the effects of different cultivation methods on the maintenance rate of food physical properties and nutrients of thick soybean sprouts after heating treatment. The maintenance rate of food physical properties was evaluated in terms of masticatory properties during eating.The resistance of thick bean sprouts to heating treatment was high after immersion cultivation inrotary bed cultivation (RC), rotary bed and CO₂ irradiation combined cultivation (RCC) and phytohormone-mixed solution (PC) that produce thick soybean sprouts with excellent food physical properties and high nutrient contents in the fresh state (immediately after harvest). On the other hand, the resistance to heating treatment was low after the routine cultivation method (Control) that allows rapid growth and CO₂ irradiation cultivation (CO₂) that is inferior in growth inhibition. The maintenance rate of the 3 major nutrients and water-soluble vitamins (VC, VB₁, VB₂, Niacin) was affected by heating time (minute) than by heating temperature. The maintenance rate of the 3 nutrients was high after RC, RCC and PC. Among the 3 nutrients, fat showed the highest maintenance rate, followed by sugar and protein. The maintenance rate of the water-soluble vitamins was much higher after RC, RCC and PC than after Control or CO₂. However, the elution rate of these nutrients into the boiling water and broth (juice) during heating treatment was marked. As to the total maintenance rate of the nutrient contents on the heating treatment, RC, RCC and PC showed excellent results compared with Control and CO₂, suggesting the usefulness of these methods. The comprehensive heating treatment resistance of thick soybean sprouts was high after RC, RCC and PC that are artificial growth inhibition cultivation methods producing excellent thick soybean sprouts in the fresh state in terms of food physical properties and nutrients. These methods are appropriate as cultivation method of thick soybean sprouts for heating treatment.

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β-Cryptoxanthin, known as provitamin A, is attracting attention because it was recently found that β-cryptoxanthin had strong anti-tumor promoters ability. About half of carotenoids contained in Satsuma Mandarin juice are β-cryptoxanthin. In the production process of Satsuma Mandarin juice, the juice is centrifuged to remove extra pulp. The pulp, discharged from the centrifuge, contained 8.25 to 13.79 mg/100 g of carotenoid. The content was as high as one of Satsuma Mandarin peel. Then, we studied the reduction rate of insoluble solid and carotenoid content of the juice in several centrifuging conditions. We found that reduction rate of carotenoid was different from one of insoluble solid, even in the same centrifuging condition. Taking advantage of the difference, we succeeded in fractionating the pulp in high carotenoid pulp (30.18mg/100g) and low carotenoid pulp (4.66mg/100g) by double centrifuge of the juice. The high carotenoid pulp was useful, not only for an efficacious extraction source for β-cryptoxanthin, but for a carotenoid additive for several foods.

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Relationship between preference and a processing method in tomato juice was examined to comprehend the recent trend of consumer preference and to obtain information available for the improvement of present processing techniques. As the result of sensory test, it was recognized that tomato juice which have a faintly grassy-smelling flavor, palatable taste, mild feature of throat, sweetness and umami, tended to be preferred. Addition of glutamic acid (sodium salt), sugar and salt into tomato juice improved the preference. Especially, salt was a important factor effective on the preference. Also, the difference in varieties used as materials influenced on the quality characters of juice, and changed the consumers' preference for them. There was no effect of ultra-high hydrostatic pressure treatment on the preference for tomato juice. The fresh fruit strains, which contained sugar at higher level, were not necessarily to improve the palatability of tomato juice. These results indicated that it would be possible to expand the consumption of tomato juice furthermore by the proper reforming of processing methods as well as materials.

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One of the yeasts isolated from Umezu which was by-product of Umeboshi making, was identified as Pichia anomala, which caused to deterioration of products. For repression on the growth of the yeast, antifungal activities of some reagents were examined by changing concentrations, kind of culture and the salt (NaCl) concentration. The minimum inhibitory concentration in the Umezu solution containing 10% salt was 1% of citric acid, 6% of ethanol, 0.3% of acetic acid, 0.004% of potassium sorbate and 0.001% of thiamine dilaurylsulfate, respectively. Using potassium sorbate or acetic acid at the pickling of fresh Ume (Japanese apricot), low-salted Umeboshi could be obtained.

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A continuous grain rotator which was equipped with a vibrating tray at a variable slope was developed for sterilization of dry food ingredients. The doses necessary for soft-electron (low-energy electron) sterilization of rice, buckwheat, wheat, tea leaf and black pepper with this continuous rotator were much lower than those with a batch-type grain rotator and at almost the same level as the doses for gamma-ray sterilization. The results suggest that the continuous grain rotator enables efficient soft-electron sterilization.

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