Three-Dimensional Spectral Imaging System (3D-SIS) was developed in order to visualize the internal structure and constituent distribution of food. A spectral illuminator and a spectral imager were installed so that fluorescence intensities at any excitation and emission wavelength at any point on the sample surface can be acquired. In addition, the sample can be sliced with a few-micron-thickness continuously by a special built-in microtome to observe all slices of the sample. As a result, a series of fluorescence data (which is called Excitation-Emission Matrix; EEM) at any point of the sample was acquired using 3D-SIS. By assigning different colors to each point of the sample with a correspondence to its EEM pattern, the internal structure and constituent distribution of the sample could be visualized. A soybean was measured and its internal structure on three growth stage was visualized using this technique.

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Isothermal calorimetry was applied to detect the heat of aging of cooked rice with Thermal Activity Monitor 2277 (Thermometric AB, Sweden). The exothermic curves due to the aging of the ricer stored at 10°C had a peak at ca. one day, the heat was mostly evolved within 3 to 4 days, and then they gradually approached zero after a week. The exothermic curves clearly indicated that (1) the heat of aging of Hitomebore was reduced when emulsified oils (Delicalight and Ricegood) or sucrose fatty acid ester (abbr. sugar ester) was added on cooking, (2) the heat of aging of Koshihikari was remarkably smaller than that of Hitomebore, and the anti-aging effect of sugar ester was small, and (3) heat of aging was not detected at 25°C. The depression ratio (r) of aging caused by the additives was estimated. Texture profiles were also examined with Yamaden Rheoner RE-3305. Typical stress (p)-accumulative strain (ε) curves of a single Hitomebore grain showed that the hardness markedly increased, the brittleness appeared, and the adhesiveness decreased with storage time. Sugar ester gave a less pronounced increase in hardness. The variations in hardness and in relative frequency of brittleness were characterized by the noticeable increase in a few days. The hardness-depression effect of the additives for Hitomebore was to be noted. The hardness of Koshihikari (25% deformation) was similar to that of Hitomebore cooked with the additives, while sugar ester gave little effect to the hardness of Koshihikari. These findings were consistent with the thermal behavior.

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The seeds of Japanese horse chestnuts (Aesculus turbinata) contain large amounts of mixed triterpenoidal saponins called "escins". Recent studies have shown that escins have several biological activities including anti-inflammatory action and inhibitory effect on the absorption of ethanol or glucose. For the edible utilization of the seeds, the seeds are usually treated with wooden ashes to remove harshness. Here, we found the novel compounds derived from escin in the seeds of horse chestnuts after the food processing with wooden ashes. The instrumental analyses revealed the chemical structures of four types of the escin derivatives. Those were identified as deacetylated forms of escins I a, II a, I b and II b. However, tigloyl and angeloyl moieties of escins were more resistant to the hydrolysis with wood ashes. To determine the biological activity of deacetylated forms of escins, the fraction including four types of deacetylated escins was used for an oral glucose tolerance test in mice. The analysis revealed that a single oral administration of 300mg/kg of those saponins was effective to show significant hypoglycemic activity. Taken together, the results suggested the potential usefulness of the saponins generated during the food processing of horse chestnuts with wooden ashes for functional food.

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As a scientific method of distinguishing cultivation methods of agricultural products, an evaluation method based on the ratio of the stable isotope of nitrogen (¹⁵N/¹⁴N, demonstrate as δ ¹⁵N value) was developed. (1) δ ¹⁵N value of the nitrogen contained in free glutamic acid (Glu) or free aspartic acid (Asp), extracted from the spinach cultivated with different amounts of organic and chemical fertilizer, were measured by a gas chromatograph-combustion-isotope ratio-mass spectrometer (GC/C/IRMS). (2) From the statistically significant results that δ ¹⁵N values of Glu and Asp become large according to the increasing amount of applied organic fertilizers, distinction of whether the organic fertilizer have applied to the spinach was presumed from δ ¹⁵N measured value. (3) That δ ¹⁵N value of whole spinach becomes large according to the quantity of the applied organic fertilizer presumed that it was because heavy nitrogen is accumulated in Glu and Asp which constitute protein or in a free state.

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Some chemical and physical properties, including the texture, of three kinds of wash-free rice (WFR) were compared with those of the conventionally milled rice (CMR). By scanning electron microscope, some exposed cell walls were obserbed on the surface of WFR, on the contrary the surface of CMR was covered with bran layer. Contents of crude protein, crude lipid, ash and sucrose of WFR showed lower than those of CMR. The hardness, the stickiness and valance values (stickiness/hardness) of cooked WFR were not significantly different from those of washed and cooked CMR. These facts supported that external bran layer was sufficiently removed from the surface of WFR. On the other hand, more scorched part was obserbed when one kind of WFR was cooked after soaking for 18hr. In this case, more reducing sugars and free amino acids were shown in the soaking water. These reducing sugars and free amino acids would make more scorched part by Maillard reaction in cooking.

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We purchased ten imported processed foods commercially available at supermarkets and retails in Metropolis of Tokyo and Kanagawa prefecture and qualitatively analyzed whether five specified raw materials were present in those by using immunochromatography based on the instructions of the kit (NANO TRAP: ROHTO Pharmaceutical Co., Ltd.). Those processed foods were also quantitatively analyzed to see if the specified raw materials were included by using ELISA kits (Morinaga Institute of Biological Science), and both results were compared to study usefulness of the immunochromatography assay. Good correlation was obtained in all test kits except Karinto with difficulty in measurement and 10μg/g or more of all the specified ingredients were detected in both ELISA and immunochromatography. There were false-positive results slightly in cookies, potato chips, chocolates, caramels, cakes, noodles, nuts, shrimp rice crackers, and ice cream using the immunochromatography assay. Our study showed that immunochromatography was useful in simply screening presence or absence of specified raw materials in commercially available processed foods as well.

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For screening of miso with antimutagenic activity, twenty one koji mold strains (each strain as Aspergillus oryzae: commercially used for making miso or sake) and the common tane-koji as control strain were used to ferment miso under the same and ordinary conditions, independently. Each miso was extracted with 80% methanol and applied to the pre-incubate method of Ames' test for searching antimutagenic activity. In these twenty two kinds of miso, two kinds of the miso fermented with AOK 139 and AOK 138 strains had potent antimutagenic activities. Especially, antimutagenic activity of the miso extract initially fermented with AOK 139 was three times stronger than that fermented with the control strain. For searching the reason of the result, quantitative analyses of the total contents of free fatty acids and fatty acid ethyl esters in miso were performed. The miso initially fermented with AOK 139 and AOK 138 contained 1.63g/100g and 1.51g/100g of free fatty acids, respectively, while the miso initially fermented with the control strain contained 0.46g/100g. On the other hand, each of the miso contained poor fatty acid ethyl esters, because during the given fermentation yeast was not added and less ethanol contained. Furthermore, we measured four kinds of enzymatic activities in each of koji, such as lipase, cellulase, hemicellulase and pectin lyase. The koji initially fermented with AOK 139 and AOK 138 showed strong lipase and cellulase activities, respectively. From these results, AOK 139 and AOK 138 strains had the ability to produce miso with rich antimutagenic activity and these miso products were considered to be functional food meterials.

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Squash products are rich in γ-Aminobutyric acid. Animal experiments were performed in order to investigate that stress of rats and mice could be reduced by oral ingestion of a squash product. Oral administration of the squash product to rats were carried out single time and multiple times. Then the rats were given stress of smelling ether, and the quantities of adrenal-cortex stimulus hormone, serotonin and thyroid hormone in blood were measured as stress indices. As compared with the a control group without oral ingestion of the squash product, in the rats that had oral ingestion of 600mg/kg/day squash product for 6 days, the amount of adrenal-cortex stimulus hormone fell significantly and the reduction in the amounts of serotonin and thyroid hormone was eased. Oral administration of the squash product to mice were also carried out, and then thiopental anesthesia time was measured. As compared with mice that didn't have oral ingestion of the squash product, thiopental anesthesia time was extended in the test group. We concluded that when provided to rats and mice, the squash product acted on their central nerves and had the effect of relieving their stress.

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Excessive fruits of satsuma mandarin (Citrus unshiu Marc.) are usually thinned at early stages of fruit development in Japan, based on leaf-fruit ratio of about 25, to enhance fruit growth and qualities, and also to prevent alternate bearing. However, the effect of crop load (fruit-thinning time and/or degree of thinning) on fruit taste is unclear. This study aimed to clarify the relationship between thinning time and fruit taste. With delaying the thinning time, the taste became better significantly and sugar content in the juice increased in very early-ripening 'Ueno wase' and early-ripening 'Miyagawa wase'. In each parameter on the taste, "sweetness" and "palatableness" marked higher scores. Thus, fruit taste can be improved by increasing crop load of the tree in early-ripening cultivars, may be resulted from, at least in part, the increase of sugar content in the juice.

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