Rheological behavior of a series of monoglycerides (MG) in aqueous systems and the distribution of sodium chloride (NaCl) in isotropic phases were investigated. The fluid isotropic (FI) showed Newtonian flow behavior. Longer the chain of fatty acid of MG, greater the viscosity of the phase was observed. The FI viscosities of the systems of MGs which consist of the chain longer than C₁₄ increased linearly with the increase of water content, while those with the chain shorter than C₁₂ decreased with the increase of water content. The viscosities of the neat phase (N) and dispersion (Dn) decreased logarithmically with water content, and there was a remarkable change between the viscosity of the N and that of the Dn region. Both N and Dn showed plasticity. Moisture content of FI in (FI+water) showed a constant ratio to FI volume from which soybean oil (SBO) content was substracted, in any sample with various SBO content. Moisture contents of FIs were small in the samples with various MG constituents and also small in those with saturated fatty acid MGs. All NaCl was included in FI in the range of lower water content, and NaCl content in FI decreased with the increase of water content in the range of water content above the certain value of each sample (MGB 22%). NaCl concentration in FI decreased with the increase of SBO content and that in aqueous phase was constant.

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Droplet sizes, dynamic stabilities, viscosities, and effects of alcohol and sodium chloride on the stabilities of emulsions prepared from vegetable oil and water by using monocaprylin (MG 8) and monostearin (MG 18) were investigated. The O/W and W/O emulsions showed thixotropic behavior and the apparent viscosity of W/O emulsion was larger than that of O/W emulsion. The viscosities of both emulsions increased with the increase of MG content and the increasing features depend on the emulsifying equipments. The viscosities of both emulsions also increased with the increasing internal phase content. Higher the MG concentration, the smaller the droplet size was, and the droplet size distribution was affected by the emulsifying equipments. Dynamic stabilities of O/W and W/O emulsions determined by centrifugation increased with the increase of MG content and decreased with the increase of centrifuging temperatures. Alcohols (methyl-, ethyl-, n-propyl-and n-butyl-) did not influence on the stability of W/O emulsion with MG 18. The stability of the emulsion was reduced by the addition of sodium chloride. From these results, surface activity of monoglyceride which is a nonionic surfactant is considered to be affected electrostatically.

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Benzoic acid was detected by ten ppb level in sake and identified using a gas chromatographmass spectrometer. A method for measuring the benzoic acid content of sake and raw materials was investigated. This method was based on liquid-liquid extraction with ether, cleaning up by silica gel column chromatography and gas chromatographic analysis with Thermon 1000-H₃PO₄(5+0.5%) glass column. The origin of benzoic acid in sake was investigated through the manufacturing process. It was suggested that the greater amount of benzoic acid came from polished rice as raw material, but a small part of benzoic acid might be produced by microbe in koji and moromi. Benzoic acid in whole rice extremely decreased in proportion to the increase of polishing of rice and the decrease of crude lipid.

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Chemical constituents and properties of soluble proteins of mame miso (Hatcho miso) were studied by means of electrophoretic and immunochemical methods. The soluble proteins were composed of four protein fractions. The molecular weights of the four proteins were estimated at 16000 to 40000 daltons for two components, 66000 for the third one and 75000 for the fourth one. All were acid proteins having different pIs below 6.0 and antigens in common with mame koji and mame koji starter. It was suggested that the proteins having the molecular weights of 16000 to 40000 daltons were the common antigens with the enzyme proteins in mame koji and the spores of mame koji starter, while those having 66000 and 75000 daltons were the common antigens with the proteins in the mycelia of mame koji.

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Molecular weight distribution of water-soluble pectin in Satsuma mandarin (Citrus unshiu Marc.) juices was measured by using Sepharose CL-4B gel filtration. This investigation was done for the following juice samples; the juice which happened to clarify, juices from the common Satsuma and the early-ripening variety (Wase Satsuma), from later-picked fruit and the unheated one. Watersoluble pectin showed the wide distribution of molecular weight from 10⁴ to 2×10⁶. In the clarified juice, the amount of the pectin larger than 10⁵ decreased and water-insoluble pectin increased. This finding suggests that it is the pectin of larger molecular weight than 10⁵ that is insolubilized and brings about the clarification of citrus juice. Some differences were observed in the molecular weight distribution between the juice from the common and from the early-ripening variety, while the distribution was neither affected by the difference in the time of picking fruit nor by heating juice.

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Lipid composition of total lipids and fatty acid composition of each lipid in various parts of yellowtail, Seriola quingueradiata, in winter were studied by means of thin-layer chromatography (TLC) and gas-liquid chromatography (GLC). Total lipids were extracted acconding to the procedure of FOLCH et al. The total lipid content (%) was higher in external part than in internal part and in anterior part than in posterior part of meats. In viscera, the total lipid content was higher in pyloric appendages and liver than in others. Fatty acid composition of total lipids were studied by GLC and about 30 kinds of fatty acid were identified. Main fatty acids of total lipids in various parts were 18:1 acid (16.5-28.9%) followed by 16:0, 22:6, 16:1, 20:1, 22:1, 20:5 and 14:0 acids. Little differences of fatty acid composition of total lipids were recognized among various ordinary meets. 22:6 acid content (%) was higher in red meat than in ordinary meat. In viscera, much differences of fatty acid composition of total lipids were observed in various viscera. Total lipids were separated into 7 kinds of lipids by TLC and main lipid was triacylglyserines (TG, 80.7-89.0%). Fatty acid composition of TG and free fatty acids were almost similer to total lipids. On the contrary, 22:6 acid content (%) was higher in compound lipids than in other lipids.

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Effect of resting of wheat flour dough on the physical properties of Japanese traditional handmade noodle was investigated. Both tensile strength of raw noodle and shear strength of cooked noodle increased with the increasing rest period of the dough. The similar phenomena were observed for the noodle with various water absorption. The both strength, however, decreased with the increase of dough resting time for the sample with short mixing time. Structural relaxation curve was conducted by tensile test for the raw noodle prepared from the dough with different rest peniods. The tensile strength of all the raw noodle with different rest periods of the dough gave the constant value by 90 minutes ralaxation. Viscoelastic parameters were determined for raw noodle by analysing the creep curve by means of four-element mechanical model consisting of Hookean body, Voigt body and Newtonian body. From the results obtained, it is suggested that Hookean modulus and Newtonian viscosity mainly contribute to the resting effect, the increase of tensile strength of raw noodle. From all these results, two hours resting at room temperature or about one hour resting at the higher temperatures are recommended for making good noodle.

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A new noodle-cooking test apparatus which is composed of newly designed cooking cups and a kind of steam generator was developed by the authors. The conventional noodle-cooking test had been performed by using such an apparatus as composed of a cooking flask, a reflux condenser and an electric heater. Three types of noodles, which were dried buckwheat noodle, 'Udon' (a Japanese noodle) and spaghetti, were comparatively cooked by use of these two kinds of testing apparatuses to investigate the properties of the cooked noodles and the efficiencies of the experimental performances. By the new method, both the moisture contents of the cooked noodles and the percentages of the waste dissolved in the cooking water were generally smaller than those by the conventional method, when the same cooking time was applied. The new method was considered to be better than the conventional method in the view point of consistency of the cooking water temperature and easiness of the experimental operations.

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Kamaboko is a sausage-like food made from fish meat. In the present work, shearing analysis, stretching-test and jelly strength-test were done on 20 samples of commercial kamaboko by using an Instron type universal food testing machine. Correlations between shearing strength and values obtained from the stretching-test and the jelly strength-test were determined satisfactorily by using regression analysis. The best correlation (correlation coefficient, 0.881) was obtained between shearing strength and jelly strength×breaking strain values, followed by correlation coefficient 0.836 between shearing strength and jelly strength values. From the results, the application of shearing analysis seems to be useful for the purpose of evaluation of kamaboko texture.

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