Effects of dry-heated egg white on frozen Chinese Noodles were evaluated by sensory tests, rheological properties, and degree of gelatinization. The surface and cross-sectional structures of the noodles were also analyzed using a scanning electron microscope. From the sensory tests, the noodles with dry-heated egg white were improved in terms of chewing texture, elasticity, resilience, and feeling of smoothness on the palate, even after freezing. From the measurement of rheological properties, it was found that the dry-heated egg white provided elasticity, improved resilience and resistance to breaking to the frozen Chinese noodles. The dry-heated egg white was found to allow the Chinese noodles to be high degree of gelatinization even after frozen storage and to inhibit retrogradation of starch. From the electron microscope observations, the surface structure of the frozen Chinese noodles with the dry-heated egg white was revealed to have fewer gaps and to be smoother than the noodles without egg white or spray dried egg white. The cross-sectional structure of the frozen Chinese noodles with the dry-heated egg white possessed a large number of network structure of protein and was finely meshed. It was found that the dry-heated egg white reinforced the connection of the network structure.

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Collagen was separated by decalcification of red sea-bream (Pagrus major Temminck et Schlegel) scales with hydrochloric acid, citric acid and disodium ethylenediamine-N, N, N'N'-tetraacetate (EDTA) aqueous solutions. The optimal condition for the decalcification was discussed on the bases of yield of collagen and the mass of ash obtained by the ignition of collagen at 1000°C. Hydrochloric acid and citric acid could achieve the decalcification, but EDTA could not adequately. By the use of hydrochloric acid and citric acid, collagen was obtained in the yield of about 45%. The separated collagen was considered to be extremely pure and classified as Type-I collagen.

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In order to examine the structural properties of fruits and vegetables in drying process, apparent density, true density, internal porosity and specific volume on a dry basis for five kinds of vegetables, which were radish, carrot, eggplant, potato and sweet potato, were determined at various moisture content. Volume shrinkage of sample with hot air drying was related to a linear function of moisture content. The relationship of apparent density and internal porosity for five kinds of vegetables to moisture content gave two different tendencies. One was a linear function of moisture content for radish and carrot, and the other was a quadratic function of moisture content for eggplant, potato and sweet potato. True density increased exponentially as the moisture content decreased. Therefore, effects of the hardening of sample caused by loss of water and heating on structural properties of them in the drying process were estimated.

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Effects of soaking solution of bamboo charcoal on hardness and pigment stability of red kidney bean were examined. The soaking solutions were prepared by carbonization of bamboo at 500°C (dielectric), 800°C (electric) and wood (Japanese cedar) at 800°C (electric), sterilization and soaking in 10 fold volume distilled water for 24h. The each solution indicated high pH value, 8.19, 10.23, 10.14, respectively, and high electric conductivity. The high level of K, Ca, and Mg were dissolved in the 800°C bamboo charcoal solution, 30.3, 1.26, 2.33 (mg/ml). But the 0.7 value of hardness (solidity) in solution corresponded to soft water. Though the commercial deep sea water contained the higher level of inorganic cations (K; 69.0, Ca; 71.0, Mg; 200.0mg/ml) and electric conductivity than charcoal solutions, the water was neutral pH and hard water. The stability of the charcoal solution during long-term storage was prevented by filling with nitrogen gas. The red kidney beans cooked in the solution became to be soft and high anthocyanin level at 530nm compared with the beans in deep-sea water. The softening and high absorbance (at 530nm) were observed in 0.01M KOH solution (pH 12.12)>distilled water (pH 6.72)>0.01M KCl solution (pH 7.16). These results indicated that pH value was very important factor, when cooked the kidney beans in charcoal soaking solution. The DPPH radical scavenging capacity and SOD activity of the charcoal solution of cooking kidney bean did not differ from those of distilled water.

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A mixture of germinated brown rice and germinated barley (A) and a mixture of germinated brown rice, germinated barley and beer yeast (B) were puffed using a twin-screw extruder to develop high bio-functional powders. Through extrusion under high-temperature and high-pressure, fine granular distribution of the extrudates and suppression of bacterial growth were available. An increase of fatty acidity during storage was inhibited and digestibility was enhanced. The extrudates A and B contained phytic acid, inositol, ferulic acid, and dietary fibers more than the germinated brown rice. In a feeding test using SHR rats, antihypertensive effects were shown in the exrudates B. As for a panel test of bread which contained 30% of the combined extrudate powder, extrudate A bred was significantly superior to the bread of 100% of flour in texture (P<0.05) and sweetness (P<0.05) of the products. Compared with germinated brown rice, the bio-functionality was significantly strengthened in the mixtures A and B.

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We studied the lethal action of compressed oxygen gas on yeast cells and discussed its application to the sterilization processing of Sudachi juice. When the yeast cells (Saccharomyces cerevisiae IFO 10149) suspended in YPD medium were compressed directly with oxygen gas, the number of viable cells decreased rapidly and their survival rate was depressed in a short time with increasing pressure or temperature. When oxygen partial pressure was same, the sterilization rate of yeast did not alter even if total pressure changed. This shows that dissolved oxygen concentration relates to the lethality of yeast. The increase of oxidation-reduction potential of Sudachi juice with increasing in temperature closely correlates to the survival ratio of yeast. The yeast cells (Candida boidinii SYM-1) suspended in Sudachi juice could be sterilized completely when treated under the following conditions: 5.0MPa for 15min at 30°C, 10.0MPa for 5min at 40°C, and 5.0MPa for <1min at 50°C. Sudachi juice was sterilized by the treatment at 50°C without loss of vitamin C content. The method sterilizing directly with oxygen gas is superior to the usual high-pressure sterilization techniques which use pressures higher than 400MPa, because our processing is performed under lower pressures than 10MPa and does not require heavy equipments and high costs to operate.

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Waxy corn starch was modified doubly by acetylation and cross-linking with acetic vinyl and phosphorus oxychloride (POCl₃). Degree of cross-linking was varied using 0.008∼0.02% phosphorus oxychloride, and acetylated substitution was adjusted to the same degree on all starch samples. Flow properties of these starch suspensions were determined by using a capillary tube viscometer. Flow parameters of these starch suspensions were markedly changed over 1.21×10^-4% (w/w) of the phosphorus content. Logarithmic value of the consistency factor, logK and apparent viscosity, logμ_a, for the power law model, decreased with increasing phosphorus content of starch. When the phosphorus content of these modified starch (cross-linking level) was over 9.00×10^-4% (w/w), the swelling of starch granules was retarded. This led to the small change in logK and logμ_a values. Flow properties of modified starch suspensions were found to be affected rather by the cross-linking modification of starch than by the acetylated modification.

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In order to estimate the effect of sushi vinegar on texture of sushi rice, physical properties of cooked rice added with sushi vinegar (sushi rice) before and after storage under low temperature (4°C, overnight) were measured by multiple physical measurements. Sushi rice was prepared by the addition of sushi vinegar in cooked rice as soon as termination of cooking. Measurements were carried out by single-grain measurement and by bulk measurement (10g), which included low compression test (compression ratio 25%) and high compression (compression ratio 90%). Single-grain measurement was shown to be better than bulk measurement, because the result of bulk measurement was inferior in reproducibility. Among additional effects of individual ingredient of sushi vinegar (acetic acid 3% (w/v), salt 10% (w/v) and sugars 50% (w/v) (sucrose, glucose, fructose and maltose)), acetic acid increased stickiness before and after low-temperature storage compared with the addition of water. Sugars increased surface hardness after low-temperature storage. Fructose increased surface hardness most among the four kinds of sugars. In the case of mixture addition of acetic acid and sugars, high concentration of sucrose or fructose decreased the sticky effect of acetic acid to cooked rice.

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The complexes of seven beans proteins (both types of degenerated or non-degenerated) and tea catechins were prepared. The amount of the complexes obtained by the precipitation in the mixture of non-degenerated bean protein and tea extract was larger than that of the complexes prepared from degenerated proteins. Galloyl-type catechins (-)-epicatechin 3-O-gallate and (-)-epigallocatechin 3-O-gallate were main polyphenols in all complexes. The complexes showed large DPPH radical scavenging activity. The activity was presumed to be a good function of the products. Particularly, complexes prepared from the proteins of 'Kuromame', 'Azuki', 'Taisho-kintoki' and 'Dainagon' showed strong activity, which has been originated from their anthocyanin constituents. Twenty-two polyphenols were also conjugated with autoclaved defatted soybean proteins. The galloyl moieties in the polyphenols were important for the conjugation with bean proteins.

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We developed a method to measure free fatty acids in one rice grain with 4-bromomethyl-7-methoxycoumarin, a fluorescent labelling reagent for monocarboxylic acid. Free fatty acids extracted with acetone from a white rice grain were reacted with 4-bromomethyl-7-methoxycoumarin at 60°C for 2h and then mixed with 70% methanol. The remaining 4-bromomethyl-7-methoxycoumarin and the fluorescent fatty acid derivatives in the solution were separated using a solid phase extraction cartridge, Sep-Pak Plus C18, by washing with 70% methanol followed by eluting with ethanol. Fluorescent intensity in the eluate was determined with a fluorescence spectrophotometer using a excitation wavelength at 330nm and a emission wavelength at 395nm. We determined free fatty acid content in individual white rice grains stored for various periods at 30°C using the developed method. The averages of free fatty acid content in individual rice grains increased up to 20 weeks storage. The free fatty acid content in individual rice grains before storage was low and distributed within a narrow range, but in rice grains stored for 4 or 12 weeks it distributed within a broad range. The range of rices stored for 20 weeks did not overlap that of unstored rices. These results demonstrate that the developed fluorescent method can determine the difference in free fatty acid content of rice grains at different storage periods.

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Gelatinization properties of cross-linked phosphate di-ester type tapioca starch were studied by using Differential scanning calorimetry (DSC) and polarizing microscope method. Gelatinization temperature (i. e. the orderdisorder phase transition temperature showing initial stage of gelatinization) of the cross-linked starch decreased on DSC pattern compared with the native one, nevertheless, viscoamylogram observation clearly showed remarkably suppression in viscosity. With polarizing microscope observation, it was confirmed that swelling of the cross-linked tapioca starch granule was hardly detected after disappearance of the Maltese cross pattern in the granule with heating.

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