Naked barley flour, which was prepared using a pin mill, was characterized and used for the production of naked barley bread. Untouched naked barley flour has high viscosity and water absorption compared with strong flour. These characteristics may be derived from the presence of dietary fiber, which would reduce the quality and volume of bread loaf. Cellulase was added to the naked barley flour to decompose any dietary fiber that was present. The resulting bread had improved loaf volume and softness compared to bread prepared with untreated flour, but still contained 1.5 times more dietary fiber than wheat bread.

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Rice endosperm enzyme activity (α-amylase, β-amylase, α-glucosidase, etc.) is increased under low ripening temperature, suggesting effects on the taste of cooked rice. We analyzed 139 rice samples (Tsuyahime, Haenuki, and Koshihikari) from Yamagata Prefecture for optimal ripening temperature between 2009 and 2013. As a result, the coefficient of variation of eight rice endosperm enzyme activities (standard deviation/average) ranged from 0.466 (β-galactosidase) to 0.174 (β-glucanase) over the production years. Negative correlations (p<0.05) were observed between ripening temperature and rice endosperm enzyme activities: α-amylase (r=-0.749), β-amylase (r=-0.519) and α-glucosidase (r=-0.730). Whereas β-glucanase, α-mannosidase, and β-xylanase tended to be negatively correlated. This suggests that the lower the ripening temperature, the greater the enzyme activity. A positive correlation (p<0.05) was obtained between the overall sensory evaluation of cooked rice and rice endosperm α-amylase activity (r=0.392-0.535) over the 4-year period, with the highest correlation observed in 2010. Additionally, α-mannosidase (r=0.162-0.542) and β-glucanase (r=0.209-0.495) tended to show a positive correlation. Thus, these results indicated a positive correlation between the sensory evaluation scores and rice endosperm enzyme activity, suggesting that high palatability of cooked rice is correlated with increased enzyme activity.

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In order to clarify the functional difference of coffee bean extracts which non-degassed or degassed, 　we examined the effect on mouse immune function of the roasted coffee bean extracts degassed for 0-96 h. The commercial roasted coffee beans are commonly degassed. We previously found that large quantity of volatile compounds in coffee extracts were decreased by the degassing. In this study, we found that the extracts of non-degassed roasted coffee beans were enhanced serum IFN-γ, IL-2, and IL-12 production of mice, in comparison with other degassed coffee. Moreover, we found that 2 kinds of sulfur compounds and 3 kinds of ketone compounds which were decreased by the degassing, enhanced serum IFN-γ production of mice. In addition, IL-2 production was enhanced by 2 kinds of sulfur compounds and 2 kinds of pyrazine compounds, and IL-12 production was enhanced by 4 kinds of pyrazine compounds. These results concluded that the roasted coffee beans　which was shortened degassing time within 30 hours, hold enough volatile compounds for enhancing serum IFN-γ, IL-2, and IL-12 production of mice.

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Radio Frequency Alternating Current (RF) was used to pasteurize tofu packaged in plastic. RF (27 MHz, 2 000W) applied to water-packaged tofu at 40°C reduced the level of Escherichia coli at the tofu’s center and in the packing liquid by 4.5 log. We compared RF treatment to hot water immersion. Conventional heating in a 75°C water bath reduced E. coli levels at the tofu’s center and in the packing liquid by 1 log and 7 log, respectively. Heating time was reduced in RF treatment to 25% of that conventionally employed. The breaking strength of RF-treated tofu was equal to that of untreated tofu, while that of conventional heat-treated tofu was decreased.

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This study aimed to investigate the effects of gelatinized starch on the bread-making qualities of Yudane dough. Yudane is a type of bread dough made by mixing boiling water with flour. Various bread-making tests were performed using freeze-dried gluten and heated and gelatinized wheat starch, which was used to imitate Yudane dough. The imitation Yudane dough was prepared by mixing gelatinized starch, prepared by heating a mixture of wheat starch and water from 55 to 80°C in increments of 5°C, with freeze-dried gluten. The heat treatments partially or completely gelatinized the wheat starch in the imitation Yudane dough. The imitation Yudane dough was then added to flour dough at 20% (w/w, flour base). Compared with the control dough (without Yudane), the dough mixed with Yudane dough had lower gassing power, gas retention, and specific loaf volume. These significant reductions in bread-making quality were mainly related to the inhibition of gluten network formation during dough mixing by the gelatinized wheat starch present in the imitation Yudane dough. In addition, the bread made with imitation Yudane dough (gelatinized wheat starch) showed dark-brown crust, caving, a slow staling rate, as well as the major features of bread made by the normal Yudane bread-making method.

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