Effects of addition of egg white or potato starch on texture of fish meat gels were studied. The various gels were prepared by cooking the mixture of egg white or potato starch and horse mackerel meat surimi with or without 20% water. Physical properties of gels were examined by texturometer tests, penetrometer tests and sensory tests. The drip during cooking was measured and histological structure of gels was observed by a microscope.
In sensory test, fish meat gels were judged to became softer, juicier and coarser as the increase of the egg white, while they were judged to be hard and fine in the case of addition of starch to the fish paste. The hardness of gels by the texturometer test became lower and penetration rate became higher as the increase of the egg white, but the drip was not changed. As the starch added increased, the hardness of gels became higher, and fragility became lower and further the drip decreased. The starch granules in the fish gels were considered to prevent the drip of surimi by swelling during cooking.

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Changes in green beany flavor in soybean sprouts were investigated as a function of time during thermal cooking. The cooking of soybean sprouts for 1 min at 100°C resulted in 95% decrease of the level of n-hexanal (a main factor of green beany flavor) in water-extracts from both the hypocotyl and the cotyledon. Lipoxygenase (a key enzyme of n-hexanal formation) activity of both parts decreased during the cooking, and change in the activity was similar as that in n-hexanal level in waterextracts from both parts. Sensory evaluation of soybean sprouts after the cooking was also carried out. The green beany flavor disappeared after 5 min of cooking and the characteristic texture of the hypocotyl lost beyond 10 min.

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The effects of added tocopherol (Toc) and silicon oil (dimethyl polysiloxane KF 96) on the thermal oxidation of oils and methyl oleate were investigated. Addition of Toc to oils (soybean, hardened soybean, olive and high oleic safflower oils) and methyl oleate were carried out before heating and after heating 1,3,5,10 and 20 h at 180°C, respectively. Oils and methyl oleate containing Toc were heated at 180°C for 30 h (soybean and hardened soybean oils),10 h (olive and high safflower oils)and 5 h (methyl oleate), and Toc content, anisidine and carbonyl values of heated oils were determined by HPLC and JOGS official method 2.4.26-81,2.4.22-73, respectively. The ratio of preventive effects against the thermal oxidation of heated lightly hardened soybean oil increased according to the amount of Toc added. The thermal oxidation of each oil was greatly depending on addition of Toc at the initial stage after heating. The order of suppression of the thermal oxidation of methyl oleate by each Toc was as follows: γ-Toc>mixed Toc>α-Toc. Anisidine and carbonyl values of methyl oleate with mixture of Toc and silicon oil were markedly lower than in those containing only Toc and silicon oil.

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The analysis of the components of the first-class, second-class and third-class Rishiri-konbu and the first-class Ma-konbu and the sensory evaluation of Dashi prepared from these konbu were conducted to investigate the relation between the classes of konbu and the components/liking of Konbu Dashi. The results were as follows.
1. In Rishiri-konbu, the upper-class one was high in the contents of protein, free glutamic acid, free aspartic acid etc. as compared with the lower-class one. Further, the first-class Ma-konbu was high in the content of these components as compared with the first-class Rishiri-konbu.
2. No component difference was found among the Dashi of the first-class, second-class and thirdclass Rishiri-konbu. However Ma-konku Dashi was much in the elution quantity of palatable components as compared with Rishiri-konbu Dashi.
3. Difference in the elution rate of glutamic acid was not found among these Risuiri-konbu Dashi.
4. No significant correlation was found between the overall impression score of Dashi at the sensofy test and the class in a ranking. The score of Dashi prepared at 10-100°C for
5 minutes became smaller in the order of first-class, second-class and third-class, but the score of Dashi prepared at 100°C for 5 minutes became in the revefse order. 5. As an effective method for the preparation of third-class Konbu-Dashi, it was advisable to heat the lconbu in boiling water for a sufficient elution of palatable components.

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Mixing conditions of eggs in cream puff paste were studied in conection with heating degrees of flour in the paste.
The results obtained were as follows:
1) In case of properly heating the paste, specific gravity of the paste was decreased, and increment of number of air bubbles and homogeneity of the paste were observed with microscope when mixing was adequate.
2) The larger puff-crust was obtained when the specific gravity of the paste was smaller. Accordingly the air bubbles in the paste became one of the factors of puffing development.
3) Over-mixing caused decreasing the number of air bubbles by the rising of the temperature.
From these results, in mixing the cream puff paste, not only homogeneous dispersion of ingredients but also inclusion of air bubbles was found to be required. And it was suggested that the amount of the air bubble was related with the conbination of ingredients, degree of gelatinization of starch, consistency of the paste and the temperature of during mixing.

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In order to know texture type of new fishes in circulation market, experiments were carried out. Thirteen kinds of fish were selected from the new type fishes in circulation market and, as standard fish, three kinds of fish with different texture, namely skipjack, horse mackerel and flatfish were selected from the popular fishes in Japan. The physical properties of their cooked meat i. e. drip, residual weight, hardness, cohesiveness and penetration value were measured. The data obtained were analyzed by the multivariate statistical analysis. The texture types of thirteen kinds of fish were classified into skipjack type, horse mackerel type, flatfish type and the other type. The flishes of skjpjack type were jurel, pomfret and slender tuna. The hardness of them was high and their meat was juiceless. The fishes of horse mackerel type were red cod, hoki, southern blue whiting and orange roughy. This texture type was considered to be between skipjack type and flatfish type. The fishes of flatfish type were tilapia, black cod and hake. Their meats were tender and juicy. Three kinds of fish, i. e. white warehou, silver kingfish and elephant fish, were classified into none of three types. The hardness of white warehou, silver kingfish was in the middle of skipjack type and horse mackerel type but they were juicier than flatfish type. Elephant fish was the tenderest of all fish. We could presume the suitable cooking methods for each new fish in circulation market.

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Thirty samples of salted guts produced in Japan and forty six samples of salted guts in Korea were used in this experiment. The results obtained were as follows.
1. The mean values of water activity, sodium chloride concentration and viable cell counts of three kinds of salted guts produced in Japan ranged 0.578-0.767,6.46-18.70% and
2.985-4.884(log. /g), respectively, while six kinds of samples in Korea ranged 0.528-0.718,8.13-20.87% and 3.311-7.121(log. /g), respectively.2. The detection rate of coliform organisms in salted guts produced in Japan and Korea were 32.4% and 4.3%, respectively.
3.Tolerance salt concentration of Bacillus subtilis and Coliform organisms isolated from Korea salted guts was 12-14% and 6-8%, respectively, at the concentration of sodium chloride.

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The fatty acid composition of sixteen samples of salted guts produced in Japan and of fifty samples of salted guts in Korea were analyzed by using gas chromatography.
The results were as follows
1. The fatty acid of salted guts were composed of C14: 0, C16: 0, C16: 1, C18: 0, C18: 1, C18:2, C18: 3, C20: 4, C20: 5 and C22: 6. But, the major fatty acid of salted guts were three or four of them.
2. The major fatty acid of squid and shrimp made in Japan, and shrimp and pollack roe made in Korea were C16: 0, C18: 1, C20: 5 and C22: 6. Those of victorfish were C16: 0, C18: 0, C20: 5 and C22: 6.
3. The major fatty acid of squid and internal organs made in Korea were C16: 0, C18: 1, C18: 2 and C22: 6. Fatty acid of croaker and shell were C16: 0, C16: 1, C18: 1, C22: 6 and C16: 0, C20: 5, C22: 6, respectively.

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Peroxide values of small quantity of lipids in the dried gelatinized rices from the packed instant dried rice products on the market were determined and also it was checked by sensory tests whether these rices had any off-flavors or not. Then changes in peroxide values and occurrence of off-flavor during storage of these packed rices were examined. These experiments indicated that some dried gelatinized rices including baby food products on the market showed high peroxide values (140-310m equiv./kg) and had some off-flavor. As a result of the preservation tests of the dried gelatinized rices which were producted commercialy through the steam cooking and air drying process. It was ascertained that small quantity of lipids in this packed dried rices obviously showed high peroxide values (300-500m equiv./kg)after more than 0.5 month at 44°C, atfer more than 1 month at 24,34°C during storage, and with peroxide values going up this off-flavor was detected more stronger. Therefore this off-flavor was evidently caused by the lipids rancidity of these products during storage. Low moisture contents and Aw (Aw=0.15) of these products and being very porous condition caused by the air drying process of these products seemed to accelerate the lipids oxidation. But this phenomenon seemed to be different from some kind of production methods of these products. Finally it was investigated how to protect the lipid oxidations of these packed dried rices, it was found that using some antioxidants (lecithin and tocopherol) for these dried rices or enclosing a deoxidizing agents inside the packaging matterials were very efficient.

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Vol. 24 No. 1 p. 79

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Vol. 24 (1991) No. 1 p. 70

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