The foam formation and stability were measured in soy milk to identify the effects of blowing microbubbles on the cooking and processing methods. The foam formation was evaluated by the foaming power and height of the foam, whereas the foam stability was assessed by the drainage ratio and drainage rate. The foaming power increased with increasing microbubbles blowing time. A longer blowing time for the microbubbles resulted in greater foam height, although the foam height was not comparatively great for highly viscous soy milk. Increasing the blowing time resulted in a decreased drainage ratio and drainage rate, maintaining the stability of the foam. A negative correlation was found between the foaming power and drainage ratio in the early stage of drainage. The overall results show that a long blowing time for the microbubbles was effective for high foam formation and stability.
Hard meringue samples with four levels of added of sugar contents (50%, 100%, 150% and 200%) were prepared from three types of sugar alcohols (xylitol, sorbitol and lactitol) and from sucrose. We investigated the properties of the baking and hardening process in respect of physiological tests of the meringue before and after baking, change of firmness during storage, differential scanning calorimetry for hard meringue, and change under high humidity. The lactitol meringue with high sugar content showed the highest compression stress before baking. However, the hard lactitol meringue was softened most easily by absorbing moisture from the surroundings. The baked sorbitol meringue hardened slowly to finally produce a very firm texture. DSC measurement showed that a different type of crystal from that in the original sorbitol was formed in the hard sorbitol meringue. The hard xylitol meringue had moderate firmness and, like the sucrose meringue, was little influence by storage under high humidity. Xylitol was consequently judged the most suitable sugar for hard meringue after sucrose.
The active oxygen scavenging activities of katsuo-dashi were investigated. The fractions that were separated by porous-polymer resin and such compounds as anserine（Ans）, histidine（His）and creatinine（Crn）were also identified. The superoxide-anion, hydroxyl radical, singlet oxygen and peroxyl radical were used as active oxygen species. Katsuo-dashi and the fraction non-adsorbed to the resin scavenged all four active oxygen species. Creatinine strongly scavenged the superoxide anion. This result indicates that creatinine could stop the continuous reaction following the hydroxyl radical. Ans and His strongly scavenged the hydroxyl radical, singlet oxygen and peroxyl radical.
The bread-making quality of the flour produced in Gifu (Chugoku 152) was examined in relation to the granulesizes prepared with two different mills, a roll mill (Chugoku 152-I) and a test mill (Chugoku 152-II). Such properties as the granule size, color and bread-making quality were compared between the two samples. The respective mean granule sizes for Chugoku 152-I and 152-II were 95.5 μm and 56.9 μm. The granule size distribution was also different between the two, indicating that Chugoku 152-I contained bran. There was also a noticeable difference in color. The specific volume was higher for Chugoku 152-II than for 152-I, while the color difference of the bread was greater than that of the flour. Creep test results showed that Chugoku 152-II was markedly different from 152-I and closer to 1 CW. Chugoku 152-I produced poor bread quality in crust color and tint, while the sensory evaluation indicated Chugoku 152-I to have poorer quality than 152-II in all factors except aroma.
We clarified the characteristics of frying oil that had reached a flavor score of 3 from the deterioration index and sensory evaluation. Three types of food were deep-fried with or without a batter coating, and analyses of color, acid value (AV), anisidin value (An.V), carbonyl value (CV) and viscosity, and a sensory evaluation of the flying oil were all conducted. The relationship among the analytical results was examined. This showed correlations between AV and the color, An.V and CV, between An.V and viscosity, and between CV and viscosity. There were also correlations between the deterioration index, CV, An.V and viscosity, and the rancid flavor from the sensory evaluation. On the other hand, An.V, CV, viscosity, and the rancid flavor showed no correlation with AV and the color. These results revealed that oil with a flavor score of 3 could be judged by using the rancid flavor as an index for the sensory evaluation, and that the characteristics were influenced by An.V, CV and viscosity.