A raw egg was analyzed by the differential thermal analysis (DTA). Consequently, the egg yolk showed a single endothermic peak, which began about 69°C, had a center at 81°C, and was over about 90°C. The base line slanted a little at 60°C. The egg white was separated into a thick white and a thin one. Although their thermograms were different, they had the same two endothermic peaks. The one was called the first absorption peak, which began from about 61°C, had a center at 65°C, and was over about 70°C. The other was called the second absorption peak, which began from about 73°C, had a center at 79°C, and was over about 84°C. The phase transition was observed together with the first absorption of the thin white, but was not observed in the thick one. The thin one was thermodynamically in a state of equilibrium to the 13% glycerol aqueous solution under 60°C and its properties were similar to those of an aqueous ovalbumin solution. Since the thermogram of the thick one added 3% NaCl resembled closely to that of the thin one, it was considered that the thin one was equivalent to the thick one whose phase had been changed.

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A procedure to recover the isoflavones, such as daidzin, daidzein, genistin and genistein, from the cooking drain which was obtained in the manufacturing process of miso (fermented soy paste) from soybean, was investigated. The drain was treated with 5 kinds of adsorbent. As the result, the adsorbent of "Diaion HP-20" was most effective. After adjusting the drain to pH 4.0 with acetic acid, it was applied to HP-20 resin column chromatography. The applied resin was washed with water followed by 20% ethanol solution, and then was eluted with ethanol. By this method, the isoflavones in the 80% ethanol extract of deffated soybean flakes were purified. The isoflavones in the extract were adsorbed to the resin after diluting the concentration of ethanol to 20%, and then eluted with ethanol quantitatively.

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Penicillium sp.(strain K 29) isolated from a soil was found to produce a intracellular β-fructofuranosidase. The β-fructofuranosidase was purified to a homogeneous state in disc-electrophoretical analysis. The enzyme showed the highest activity at pH 6.0 and 45°C and was stable in the range of pH 5.0 to 7.0 at 40°C for 1hr. The enzyme hydrolyzed sucrose, raffinose and stachyose in the ratio of initial velocity of 100:6.3:2.1, but failed to hydrolyze palatinose, inulin (DP 40), maltose and phenyl-α-glucoside. D-Glucose, D-fructose and D-xylose were also Shown to be efficient acceptors in the transfructosylation reaction of this enzyme. It was shown that the enzyme could transfer fructosyl residues only to the C1-hydroxyl group of glucose, fructose and xylose.

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One of the oligosaccharides produced from sucrose by fructose-transferring enzyme from Penicillium oxalicum was identified. This oligosaccharide was isolated by column chromatographies on charcoal-celite (1:1) and Sephadex G-15. The saccharide was identified as 1-kestose by acid hydrolysis, enzyme hydrolysis, gas-liquid chromatography of partialy methylated derivatives, mass spectrometry of trimethylsilylated derivative, and ¹³C-NMR spectroscopy.

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It was well known that green colour of chlorophylls discoloured easily by acid and therefore the preservation of flesh green colour of green vegetable drinks was difficult. In order to preserve the green colour, this experiment was carried out to learn the basic data about the influences of pH and temperature on the change of chlorophylls to phaeophytins by the use of freez-dried spinach powder. Consequently it was ascertained that even at 0°C, the discolouration was considerably fast at pH below 5, but at pH over 6, chlorophylls were comparatively stable and the green colour was held for a long time at 0°C.

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Okara is a by-product of tofu manufacturing. Lactic acid bacteria was used as starter cultures in order to prevent microbiological deteriolation of okara. Yogurt was added to okara as starter coltures with or without 1% glucose. It was difficult to prevent the spoilage of okara in aerobic condition. But in facultatively anaerobic condition such as packing in a polyethylene film bag or a screw-cap bottle, okara was fermented by lactic acid bacteria, lowering its pH value below 4.2 resultng in inhibition of the growth of spoilage bacteria at least 4 days at 37°C. Dried starter of lactic acid bacteria, especially Lactobacillus plantarum was more suitable than yogurt in respect to utility. Optimum fermentation conditions for preventing the microbiological deteriolation of okara were inoculation of 106 dried lactic acid bacteria/g with 1% glucose and semi-anaerobic incubation at 30-37°C.

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Ash content is one of matters of concern in a viewpoint of breeding programme for Japanese home-grown wheat. A near-infrared diffuse reflectance (NIR) technique was applide to determination of ash in 60% extraction flours from 2 varieties of the wheat. A distinct tendency that flour of a finer particle size has a higher ash content was observed in the NIR spectrum, resulting in an unstable property of diffuse reflectance which was affected by mutural interaction of moisture in the flour with its flour particle. As a result of calibrations performed, the most accurate calibration was obtained with a multiple linear regression analysis using second derivative of absorbances at 4 specific wavelengths involving an absorbance at 2344nm which was assigend to a bran-related substance in the flour. It is possible to determine ash indirectly in connection with an inclusion of the branrelated fraction in the flour. However, prediction of ash in "unknown" wheat flours from different varieties from those used for performing the calibration resulted in serious errors on account of a bias effect between the varieties.

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Near-infrared spectroscopic technique was studied for determination of protein and 4 kinds of amino acids in rice flour. As a result of detailed search for the NIR spectra of rice flour containing different protein level, the NIR was proved to have a sensitivity to rice protein as much as wheat one. It was possible to decrease a standard error of estimation for calibrations by using a derivative absorbance, but on the contrary derivative procedure possibly makes an increment in bias in case of prediction of "unknown" samples. It was verified that the NIR technique had a potential for a rapid method for analysis of protein and amino acids contents in rice flour.

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Foaming properties of egg yolk low density lipoprotein (LDL) were compared with those of ovalbumin, a typical globular protein of egg white. Foaming power of LDL was almost the same as that of ovalbumin, but its foam stability was much lower. When the concentration of LDL was exceedingly high, its foamstability corresponded to that of ovalbumin. Foaminess of LDL occurred at the presence of relatively large amount of peanut oil. These characteristics of LDL foaminess were also ascertained by the measurement of surface chemical properties of LDL.

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