Evaporating process of a white bread has been studied both for radiation and convection heating system. The white bread was baked in an open condition by an electric radiation heater for the radiation experiments and by a hot air impinging to the food surface from a nozzle for the convection experiments. The variations of evaporating rate and heat receiving rate were calculated from the weight loss and the surface temperature, respectively. The evaporating rate for the convective heating was higher than that for the radiative heating throughout the baking time. The heat receiving rate for the convective heating was higher than that for the radiative heating at the first period of baking. But, it decreased rapidly and then became lower than that for the radiative heating. The calculation of the energy balance of the bread at baking showed that 60% of the received energy was used for evaporation at first both for convective and radiative heating systems. In the case of the radiative heating, its value decreased with time. On the contrary, in the case of convective heating, its value increased to 90% and then decreases with time. It means that the evaporating process is governed not only by the received energy but also by the heating manner.

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Glycated globins, which were prepared with porcine globin and various monosaccharides (glucose, arabinose or fructose), were obtained and its properties were investigated. 1) The Maillard reaction occurred between globin and monosaccharides. It was shown that the glycation rate depended on the kind of saccharides by measurements of modification rate of the amino groups and SDS-PAGE analysis : 2) The solubility of glycated globin prepared by 24 h-glucose modification was 1.4 times as much as that of globin at pH 5.0. The solubility of globin increased after 12 h-fructose modification, while the 12 h-arabinose modification remarkably decreased the solubility : 3) The gel strength of globin declined with the Maillard reaction time even if any monosaccharides were used : 4) Emulsifying activity of globin increased when the glucose modification was made for 72 h. The 12 h-fructose modification also enhanced the emulsifying activity slightly. However, the 12 h-arabinose modification provided the poor activity : 5) For antioxidative ability of globin against linoleic acid, the glucose or the arabinose modification increased this ability. On the other hand, the fructose modification promoted to decline the antioxidative ability as the Maillard reaction time increased.

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The effects of proanthocyanidin (dimer and trimer) isolated from BPE (a polyphenol extract from barley bran) on hyaluronidase activity, soybean lipoxygenase activity and complementary activity in vitro were studied in comparison with catechins. Inhibition to these activities was depended on BPE concentration. Inhibition of proanthocyanidins to hyaluronidase was more effective than that of (+)-catechin, (-)-epicatechin and (- )-epigallocatechin, however, less effective than that of (-)-epigallocatechin gallate ((-)-EGCG) and (- )-epicatechin gallate ((-)-ECG). The inhibitory effects of proanthocyanidins on lipoxygenase activity were found to be higher than those of catechins. The anti-complementary activities of proanthocyanidins except procyanidin B 3 were found to be same or more effective than those of (-)-EGCG and (- )-ECG. These results suggested that BPE and proanthocyanidins isolated from BPE might be good inhibitors to inflammation and allergic reaction.

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"Shibori Daikon" is a traditional and strongly pungent Japanese radish in Northeast area of Akita (especially Kazuno City). The major mustard oil of Japanese radish is known as (E)-4-methylthio-3 -butenyl isothiocyanate (1), but 4-methylthiobutyl isothiocyanate (2) was found to be the major pungent compound in some of Sibori Daikon samples. A simple and easy method for quantitative determination of both 1 and 2 was developed with FID-GC analysis. These isothiocyanates were extracted effectively with chloroform from the radish juice, which was the key process to prepare samples for the GC evaluation. The content of 1 ranged from 558 to 1918 μg/g radish and 976 μg/g as average of the radishes that contained 1 as a major mustard oil constituent. These results showed that the content of 1 produced in Shibori Daikon varied from sample to sample, but its amount was almost five times higher than that of Aokubi Daikon.

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With the aim of examining the effects of pasteurization and UHT processing conditions on the sensory characteristics of milk, sensory evaluation was conducted on various pasteurized and UHT processed milks as well as on commercial milks. The effects of pasteurization and UHT processing on the physicochemical properties of milk were clearly shown in the denaturation rate of whey proteins and rennetability. In the evaluation of the palatability of milk, milk pasteurized at 130°C for 2 seconds (UHT 130) was most preferred. Preferences with respect to the sensory attributes of odor as well as aftertaste and body were important for palatability, and accustomed taste was one of the factors affected in the evaluation. The results of the evaluation of sensory attributes and the principal component analysis of those attributes showed that UHT milk having strong body was assessed as having the feeling of natural milk, and the sensory attributes of odor and aftertaste were evaluated as being agreeable. On the other hand, in the case of HTST milk, as well as LTLT milk, the sensation of thinness was strong. This was assessed as being fairly characteristics of this type of milk and was inclined to give a dislike of the odor and aftertaste. The results of sensory evaluationof commercial milk by a panel of housewives were the same as the above-mentioned results by a panel of experts.

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Elastic modulus of ordinary gels such as LM pectin and gelatin generally increased with increasing of synerized water whereas that of agarose (agar) gel decreased. From electronmicroscopic observation, it was seen that the decrease in elastic modulus was caused by making ununiform network structure with syneresis. The intanglement of bundle of double helix of agarose molecular chain with syneresisformed the large voids with the shape of ellipse. Thickness of this bundle had 20 to 40nm, which did not change with syneresis.

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