The present study was planned to examine if the sweet potato leaf could utilize as a food source. The cookies containing sweet potato leaf powder were prepared, and then evaluated from the points of the quality, preference characteristics and preservation stability. The results of sensory evaluation showed that the sweet potato leaf cookie and the jew's marrow leaf one were higher in the green color and stronger in the smell like green leaf than the without leaf powder one. However, there ware no significant differences in the taste and the texture among the three kinds of cookies. No different preference for the three kinds of cookies was also observed from the total evaluation of sensory test. Further, the breaking characteristic values of the both cookies added with the sweet potato leaf and the Jew's marrow leaf powders were not different from those of without leaf powder cookie. In the preservation period of the cookie samples in a dark room at 37°C for 8 month, the green color and the chlorophyll content decreased, and the acid value and the peroxide value of the lipid fraction in cookies increased. However, these changes weren't remarkable. In summary, it was evaluated that there was almost no problem in all the quality of the cookie added with sweet potato leaf powder.

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In this study, distributions of chain-length of amylopectin and pasting properties of rice starch prepared from three kinds, namely Hypoallergenic rice, good taste Varieties A and poor taste Varieties B, were investigated. The following results were obtained. The distribution of chain-length of amylopectin, expressed as a value of Fr. 111 /Fr. III were 3. 23 for Hypoallergenic rice, 3. 22 for Varieties A and 3. 62 for Varieties B. The long-chain content of Hypoallergenic rice was especially high as 25. 0 mol% whose average chain-length was above 60 compared with Varieties A and Varieties B. The short-chain content of Hypoallergenic rice was high as 25. 0 mol% whose average chain-length was less than 10 compared with Varieties A. The average chain-length of the sum of Fr. II and Fr.III was 51. 2 for Hypoallergenic rice, showing a tendency of being longer than 21. 6 for Varieties A. The swelling power of Hypoallergenic rice was lower than the other two kinds and solubility of Hypoallergenic rice was higher than the other two kinds. The result of pasting viscosity analysis, measured by a Rapid Visco Analyser, shows that the maximum, minimum, final viscosity and break down was lower than the other two kinds.

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Tonewase'fruit is the most popular Japanese persimmon (Diospyros kaki Thunb.) in Japan. It has fine flesh and good taste after its astringency was removed. But the fruit has very short shelf life, because of rapid softening. There are two ways for removing astringency; 1) treatment with alcohol on tree and 2) treatment with carbon dioxide (CO₂). The present study was conducted to investigate the relationship between the changes in fruit firmness and β-D-galactosidase activity which was hydrolyzed hemicellulosic components. (1) The loosing of fruit firmness was not different between treatments of alcohol on tree and CO₂ at 20°C for 24 hours (CTSD method) for removing astringency until 4 days after storage at 20°C, however, the former showed slow softening during storage for 8 days but the latter was rapid softening at 6 days (5 days after treatment). The respiration and ethylene production of fruits treated with carbon dioxide and non-treatment were similar pattern and increased at the end of storage period. However, the fruit of alcohol treatment on tree maintained low level which was comparison with non-treatment and carbon dioxide fruit. (2) The activity of β-D-galactosidase which was non-treatment and CTSD treatment for removal astringency increased during storage. The fruit of alcohol treatment on tree maintained low activity during storage. Finally, the activity of non-treatment and CTSD treatment fruit was higher than alcohol treatment on tree one during storage. These results indicated that the fruit softening of 'Tonewase' is attributable to increase of ethylene production and attended to increased, β-D-galactosidase activity. It was suggested that the fruit softening of alcohol treatment on tree, CTSD treatment, and non-treatment fruits were depend on a degree of hydrolyzed hemicellulosic components during storage or postharvest.

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Two potato cultivars commonly used in Japan for processing, Toyoshiro and Norin-ichigo, were reconditioned at 16°C, and their sugar (glucose, fructose and sucrose) and starch contents within the tubers were measured at intervals during reconditioning. The aim of this study was to examine sugar distribution within the tubers during reconditioning. The experimental data revealed that the stem end area of both cultivars had 3. 8 and 1.1 times higher reducing sugar (glucose and fructose) and starch contents, respectively, than the bud end area during reconditioning.

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Effects of cellular components on the chlorophyll (Chl) degradation in radish cotyledons were studied to clarify the mechanism of Chl degradation. Chls content of cotyledons decreased greatly during storage at 25°C in the dark. A slight decrease of Chl a content, however, was observed in the chloroplasts during the incubation at 25°C in the dark, whereas Chl a content decreased greatly in the cotyledon homogenate. Pyropheophorbide a, in particular, as a derivative was formed with the Chl a degradation in the cotyledon homogenate. These results indicate that the cellular components outside chloroplasts might relate largely to the Chl degradation in radish cotyledons.

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Enterococcus faecium MR006 was isolated from Miso and found to produce a bacteriocin with strong antibacterial activity. A culture of E. faecium MR006, maintained at a constant pH of 6.0 or 7.0 at 30°C, exhibited bacteriocin activity two-fold higher than that of the same culture grown under pH-uncontrolled conditions. MR006 bacteriocin was purified to homogeneity on SDS-PAGE by hydrophobic column chromatography and gel filtration. The estimated molecular weight of the MR006 bacteriocin was approximately 5.5 kDa, based on the tricine-SDS-PAGE system. Amino acid sequencing analysis revealed that the bacteriocin was identified to enterocin B, which is a bacteriocin produced by E. faecium T136.

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The objective of this study is to develop low-salt hybrid sausages with soy protein using pressure processing. The quality of soy-hybrid sausages were modified by changing pressure (0-500 MPa), NaCl concentration (0, 1.0, 2.5%) and the amount of soy protein (10-40%). Water holding capacity of soy-hybrid sausages increased with increasing amount of soy protein regardless of the application of the pressure treatment. However, the gel strength and the work done values decreased proportionally with the amount of soy protein added. The largest pressurization effect was observed, when the pressure processing was performed at 200 MPa with 1 % salt. With the treatment at 200 MPa, the gel strength and the work done values of soy-hybrid sausages with 1% salt were almost identical to 2.5% salt soy-hybrid sausages. When NEM was added, the gel formation was clearly inhibited in pressure-treated soy-hybrid sausages with 1 % salt. This result strongly suggests that the S-S exchange reaction of SH group increased by pressure treatment and that this increase played an important role for the gel formation of soy-hybrid sausages with low salt concentration. According to sensory evaluation, it became clear that the pressure-treated soy-hybrid sausages at low salt concentration (1.0% NaCl) with 10% soy protein had almost the same quality of pork sausage at usual salt concentration (2.5% NaC1). These results show that using pressure treatment at 200MPa produced good quality soy-hybrid sausages without excessive salt, as well as food additives such as phosphates.

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