The dewatering process of agar-agar gels comntaining sucrose was experimentally investigated by using a compression-permeability cell. The gels used in the present study were agar-agar bulk gels prepared from agar-agar sols by adding powdered sucrose. The bound water in the gel matrix was quantitatively evaluated by measuring the electrical conductivity of the agar-agar gels containing sucrose. The maximum bound water contents was obtained at the sucrose concentration of c_s=20 wt. %, where the bound water content corresponded to 2.0-fold mass ratio of the dry gel solid. The dewatering process of agar-agar gels containing sucrose by mechanical compression could be reasonably analysed as a cake filtration period followed by a consolidation period. Both average specific filtration resistance α_av, and modified consolidation coefficient C_e were well correlated with applied pressure p and viscosity of sucrose solution μ. It is essential to take into account the bound water content in the analysis of the expression process for agar-agar gels containing sucrose.

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The effects of the addition of "Tobiko" (flied powder) on the mechanical properties of Konjac gel and microstructures of the sol were investigated by creep and rupture tests, and observation with a scanning electron microscope (SEM, S-800). The results obtained were as follows:
(1) By increasing the amount of "Tobiko" added to "Seiko" (isolated powder), the values for the mechanical parameters corresponding to Konjac's hardness and viscoelasticity decreased. The elastic modulus of Hookean body for Konjac decreased in proportion to the amount of "Tobiko" added, but the elastic modulus of Voigt body and the viscosities of Newtonian body showed the different behavior.
(2) The mechanical parameters of Konjac increased remarkably by the addition of "Tobiko" at relative rations above 80% to "Seiko".
(3) SEM observation revealed that "Seiko" sol had a thick (1.5-2μm) branched network microstructure, and the fibrous microstructure became thinner and a stitch became larger when "Tobiko" was added to "Seiko". By aging at 90°C, the particles of Konjac starch disappeared through gelatinization, and the smooth fibrous microstructures were observed.

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Recently, the authors developed novel assay methods of superoxide dismutase, WST-1 method and chemiluminometric FIA (CL-FIA) method. In the present investigation, those two methods were applied to estimate superoxide anion-scavenging activity (SOSA) of foods and the results were compared with those by ESR method. Red wine, green tea, cocoa and coffee were used as the sample. The first one is the colorimetric method using highly water-soluble tetrazolium salt (WST-1). The dilution ratio giving 50% inhibition (IC₅₀) of each sample by the WST-1 method was as follows: red wine, ×180-230: green tea, ×3000; cocoa, ×230; coffee, ×210. Although direct reduction of WST-1 with food components was observed without involvement of superoxide anion, the extent of the non-specific reduction was less than 3% in those dilution ratios. The second one is the CL-FIA method using chemiluminescence of lucigenin. The immobilized xanthine oxidase in a reactor was used to generate superoxide anion. This method could be a useful tool for measuring SOSA (60samples/h) much more rapidly in comparison with the other conventional methods. The following IC₅₀ was obtained: red wine, ×3800-5800; green tea, ×120000-150000; cocoa, ×4300: coffee, ×4100. The non-specific chemiluminescence was not observed in these dilution ratios. Furthermore, this system showed high stability even during 250 repetitive injections of diluted food samples. A significant linear relationship between these novel methods and the ESR method was recognized, indicating that these methods might be applicable to estimate SOSA of foods.

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The water uptake of raw milled rice grain was examined as a rapid and easy evaluation method of sensory quality of cooked rice. The water uptake of rice grains soaked for 60min showed high correlation with sensory evaluation. This finding was proved to be valid for different three crop years. It was not found to be influenced by the ripeness of rice grains. The water uptake of rice grains with different milling yield (90% and 70%) was examined, and it was found that the water uptake of 90% polished rice depended on the variety, while that of 70% polished rice was independent of the variety. It suggests that the difference in water uptake of early stage originates from the difference in structure and chemical components in outer layers of rice grains. It was found that the water uptake of rice grains increased with decreasing amylose content.

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Remarkable deterioration on quality of Yuba food products which is prepared by conventional commercial sterilization, such as browning reaction derived from Maillard reaction, texture change of proteins, and oxidation of lipids, due to the heating treatment under severe sterilization condition. Thus, in order to improve the quality of Yuba food products, an identification of spore-forming bacteria which is present in a soybean and Yuba was performed, and the control of microbes was attempted by combined use of heating treatment and addition of nisin. The major species of spore-forming bacteria in Yuba was estimated to be Bacillus lichenifomis which was present in soybean. Application of the heating treatment (F₀=0.8-2.5) and the addition of nisin (150-250μg/ml) enabled sterilization condition to be milder, and also was effective for the complete inhibition of germination of B. lichenifomis to manufacture the satisfactory product in quality, color and texture.

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Properties of buckwheat flour made from cold counter-jet-mill (CJM) were compared with those from roll-mill (RM) flour. The CJM flour contained 13.7% protein and its average granule size was μm. The CJM flour expanded to 2.8 hold of original volume in excess water. A cooked noodle made from CJM flour showed a long and unbroken line, but that made from RM flour broke into smaller one by boiling and washing. An odor sensor data of CJM flour differed from RM flours by means of principal component analysis.

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Four cultivars of wheat (Bandohwase, Norin 61, Tsurupikari, Ayahikari) were cultivated in various cultural conditions or harvest times. These grains were ground to 60% extraction flour (A flour), and color value (L*, a*, b*) and mineral contents (Ca, K, Mg, Cu, Fe, Mn, and Zn) were analyzed. There were two types of correlations between mineral contents of flours and their color values. In first case, increasing of Mg, Cu, and Zn contents in flours were observed according to the decrease of the L* value caused by increasing an application of nitrogen fertilizer. In another case, decreasing of Ca, K, Mg, Zn contents and increasing of Fe contents in flours were observed according to the decrease of the L* value of as a harvest time was delayed. Decreasing of the L* value was observed according to the increase of iron contents in flours. Correlation between the iron content and the L* value was observed, the range of coefficient of correlation being 0.70-0.84. Therefore, it is suggested that iron was related to the color of wheat flour.

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Adductor muscle of scallop (Patinopecten yessoensis) possesses a pleasant taste and texture. However, variations of commercial foods of scallop are few. Fermentation technique has never been used in the food processing of scallop. This paper presents a processing method for gelatinizing minced scallop with lactic fermentation. Minced scallop were fermented at 20°C for 4 days with addition of a dried starter of lactic acid bacteria, Lactobacillus plantarum JCM 1149^T. This lactic acid bacterium grew well in the minced scallop, and gently decreased its pH, and gelatinized minced scallop. Gelatinized scallop had a texture similar to kamaboko and was slightly tart in taste.

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