The inflation phenomena due to brief microwave irradiation on albuminous materials with alimited amount of water involve remarkable changes in their rheological properties. To investigatethe inflation phenomena and the changes in physico-chemical properties of the maerials, whole egg and egg albumin compounded with various amount of water were heated by microwave andconductive ovens and examined for some properties, and the following results were obtained :(1)Whole egg and albumin, ranged in 30-40% of their initial water content, were the most inflatable asindicated by higher velocities of temperature-rise and water evaporation. (2) The samples inflated bymicrowave heating were different from those by conductive heating in the following points. (1), The rate of enzymatic digestion with trypsin was much higher. (2)The rate of deuterium-protium exchange was higher at the earlier heating stage. (3) The amount of extractive protein were ratherlowered of the samples in the limited water condition. (4) The release of lipid from whole egg onmicrowave heating was prevented much more than that on conductive heating.

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[in Japanese]

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Hot-water extracts prepared from beef, pork, and chicken bones have been manufactured for a long time, and are used in many types of products, and have a large annual production. However, a detailed examination on the manufacturing conditions has not yet been carried out. In this study, we prepared the extracts at 100°C, the most common temperature for industrial purposes, and 10°C higher and lower than that. We compared mutual relationships among these extracting conditions, on their free amino acid compositions, and their sensory evaluation of basic taste qualities and overall preference. Fluctuation in mutagenicity of each extract was also inspected in connection with their extraction conditions. In conclusion, an extraction at a lower temperature than that generally used n the seasoning industry provided us with better results not only in recovery of free amino acids and sensory properties, but also in long term safety in regard to mutagenicity levels, regardless of the species of raw materials.

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This investigation was carried out in order to elucidate the characteristics of dorsal muscles of chum salmon with low gonadsomatic index caught on the Rausu coast, Hokkaido. The contents of chemical components such as moisture, protein, lipid, ash, extractive-N, astaxanthin and mineral were determined by the ordinary method for the muscles of two males and four females. As a result, there is no appreciable difference in the contents of all the nutritive components between male and female. Proximate compositions of the muscles of male and female were 68.3±0.10% and 68.25±2.23% moisture, 16.23±0.96% and 16.91±0.93% protein, and 13.21±0.62% and 12.58±0.65% lipid, respectively. The characteristic of dorsal muscles of the chum salmon was the high lipid content and low contents of moisture and protein. In addition, the fatty acid compositions of total lipid, neutral lipid and polar lipid were determined by GLC method. The major fatty acids of total lipid and neutral lipid were C14:0, C16:0, C18:0, C16:1, C18:1, C20:1, C22:1, C20:5 and C22:6. On the other hand, the major fatty acids of polar lipid were C16:0, C18:0, C18:1, C20:5 and C22:6. The sum of these acids was more than 90% of the total fatty acids in each lipid. Contents of Fe, Zn, Cu and P were almost coincident with that of other chum salmon, and the Ca content was slightly low.

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We tried to make low calorie potato chips by ethanol treatment. Raw potato slices were dipped in 99.5% or 60% (v/v) ethanol at 20°C, 30°C or 40°C for 3 or 10 min before frying for dehydration. The potato slices were dipped in ethanol solutions by the same conditions except for 5 min after frying to extract oi1. Weight, moisture content and oil content were measured to determine the effects of ethanol treatment. L values and the general components of potato chips were analysed. Sensory evaluation and purchasing wi11 of consumers were also carried out. Dehydration of raw potato slices were significantly or slightly dependent on the concentration and temperature of ethanol treatment. Oil content of potato chips was appreciably decreased when treated with ethanol before frying. L valuesofpotatochipstreatedwithethanolbeforeorafterfryingweregenerallyhigherthanthoseof untreated ones. In spite of less decrease in oil content and calorie, potato chips treated with 99.5% ethanol at 40°C for 3 min after frying were better than those treated with 99.5% ethanol at 40°C for 5 min before frying from the result of sensory evaluations and research of the purchasing wil1. From these results, it was concluded that the treatment with ethanol was suitable for decreasing calorie without spoiling flavor.

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