An internal structure of a sample soybean seed (Glycine max) was represented by using a virtual three-dimensional (3D) visualizing method. This method is a combination of sequential sectioning, autofluorescence imaging in digital and displaying as a virtual representation model by the 3D accumulation of section images using a personal computer with volume rendering process. By the autofluorescence imaging, the distribution of fluorescent tissues was observed in each section. By using the virtual 3D visualizing method, the autofluorescent tissues were observed to form a spriggy 3D structure in the soybean seed. Comparison of the 3D location of hypocotyl with such distributions, indicates that autofluorescent tissues are tissues which will become vascular bundles of cotyledon after germination.

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The effects of addition of thickeners (0.5-2.0%(w/w)) and agar with concentration of 0.4-2.0%(w/w) on rheological properties of agar gels treated with freezing-thawing were investigated by measurements of dynamic viscoelastic, breaking properties and syneresis. Guar gum, ι-carrageenan and locust-bean gum were selected as thickeners. The rupture stress and storage modulus E' of post-thawing gels without thickener increased with agar concentration (p<0.01). The syneresis of 2.0% (w/w) agar gel after thawing was smaller than that of 0.5% (w/w) and 1.0% (w/w) agar gels (p<0.01). The rupture stress and storage modulus E' of all post-thawing gel decreased owing to the adding of guar gum (p<0.01). The rupture stress of gels after thawing increased by adding locust-bean gum (p<0.01). The loss modulus E" of gels with and without thickeners after thawing was higher than that of pre-freezing (p<0.01). The syneresis of gels after thawing decreased by addition of ι-carrageenan or locust-bean gum (p<0.01).

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The live-bacterial drug use here is a medicine for intestinal disorders containing 3 bacteria, Streptococcus faecalis T-110, Clostridium butyricum TO-A and Bacillus mesentericus TO-A. Male Sprague-Dawley rats were fed the drug for 3 weeks to examine its dietary effect on their lipid metabolism and immune function. In lipid metabolism, we found that serum triglyceride level was significantly low in the rats fed the drug. In immune function, serum immunoglobulin (Ig) levels and Ig productivity of spleen lymphocyte were not affected by the drug feeding. On the other hand, Ig productivity of mesenteric lymph node was significantly affected by the drug feeding, but the IgA level in the feces of the rats was significant decreased. These results suggest that the live-bacterial drug modulates lipid metabolism and gut immune system of rats.

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Effects of heat-dry treatment at 160°C for 60min (HDT160) or heat-moisture treatment at 120°C for 60min (HMT120) on physicochemical properties of pastes and gels prepared from heat treated rice flours were investigated. Storage modulus (G') of 10% (w/w) HDT160 rice flour paste was higher than those of untreated (UT) and HMT120 rice flour pastes. The flow characteristic parameters of the pastes were calculated by using Herschel-Bulkley equation of the scaling law model. The pastes showed pseudoplastic-flow with a yield stress. Yield stress and apparent viscosity of HMT120 rice flour paste was smaller than those of UT and HDT160 rice flour pastes. HMT120 rice flour paste easy to flow compared with pastes from UT or HDT160. Some peaks were observed in the X-ray diffraction pattern of 20% (w/w) HMT120 rice flour gel, due to amylose-lipids complexes developing thermal stability after heat treatment. HDT160 and HMT120 rice flour gels were harder and more brittle than those from UT, similar to those of sweet bean paste. Investigation of retrogradation process using by β-amylase and pullulanase method showed that HDT160 and HMT120 significantly accelerated retrogradation of starch in rice flour gels, especially in the initial stage of storage period.

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Torsional fracture properties of heat-induced milk whey protein gels were investigated in order to seek possible links with microstructures in gel networks, precursors of which were visualized using atomic force microscopy (AFM). The stress-strain relationships determined based on torsional deformation tests were confirmed to be approximately expressed by a linear function for all examined gels. Gels formed at pH 2 were brittle with small fracture strains and large elastic moduli, while those formed at pH 7 exhibited much larger fracture strains and smaller elastic moduli. AFM allowed observation of strings of beads structures, composed of linearly aggregated globular protein monomers, as gel precursors formed at pH 2. At pH 7, aggregation appeared to proceed in two steps; that is, the formation of particulate primary aggregates, the diameter of which is several times larger than that of the protein monomer, followed by random aggregation among those primary aggregates. These results suggest that macroscopic mechanical properties of heat-induced whey protein gels reflect microstructures of gel networks on the nanometer scale.

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A new grain and an old grain of rice were stored at low temperatures (-1°C, -5°C) for 60 days. They were examined over the period by physicochemicaly and with sensory analyses, what factors for taste improvement were studied. Significant differences were observed on the total sensory results, appearance, flavor, taste, and stickiness, when the old grain with moisture content adjusted to a middle level was stored for 60 days. It was found that the taste improvement was associated with moisture content, L value of color (brightness), free carbohydrate contents, free amino acid contents, flavor discernment, setback value, and the final viscosity. It will be possible to improve the taste of old rice grain by utilizing these findings.

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For the investigation of physical properties of the internal-browning-affected fruit, un-bagged 'Fuji' apple fruit was sealed in stylofoam box with methyl bromide (MB). Internal browning was detected in all fruit treated with MB. No significant difference in flesh firmness measured by ordinary destructive methods was detected between MB-treated and non-treated fruit. In the MB-treated fruit, the frequencies of 2^nd and 3^rd resonance measured non-destructively by a Laser Doppler Vibrometer were lower than nontreated fruit. The elastic index, calculated with the frequency of 2^nd resonance and fresh weight, total intensity of the vibration of fruit in the period from 2^nd or 3^rd resonance to 2kHz were low in the MB-treated fruit. By elastic index and gain of the vibration of fruit measured by Laser Doppler Vibrometer, a possibility of the non-destructive detection of fruit with internal browning induced by MB was suggested.

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