The characteristics of three types of mixed gels and two single gels, using mixtures of curdlan with pectin, carrageenan or xanthangum, and curdlan and pectin alone were compared. In textural properties, cohesiveness was the only attribute which differed between the five different kinds of gels. The three types of mixed gels had much lower rupture stress, rupture strain and rupture energy values in comparison with the single curdlan gel, although the initial elastic modulus was higher.
Canonical discriminant analysis clearly distinguished the single curdlan gel and the single pectin gel among the five different kinds of gels, it being difficult to distinguish among the three types of mixed gels. Scanning electron micrography revealed the structure of the single curdlan gel to be in the form of microfibrils, while the single pectin gel had a densely connected thin-plate structure. The mixed gels had a net-type structure, each being distinguished by the thickness and density of the fibers.
The sensory evaluation demonstrates that the three types of mixed gel had many similar textural properties, the single curdlan gel was tough, hard, not adhesive and not crisp, while the single pectin gel was quivery, soft and adhesive.

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The cause of deterioration of expansion in chou crust baked from the preserved chou paste (CP)under the condition of high temperature for a long period was investigated. When CP, which was prepared using shortening, water, wheat flour and egg, was stored at 20°C for 24 h or at 30°C for more than 3 h, the expansion of chou crust was less than that of CP which was bafed immediately after preparation. The same phenomenon was observed when CP, which was prepared using wheat starch instead of wheat flour, was preserved at 20,30 or 50°C for 24 h. Although, the usage of CP which was prepared by using egg stored at 50°C and fresh starch paste, induced a deterioration of the expansion of chou crust. CP prepared using fresh egg and starch paste stored at 50°C did not bring about any deterioration. These results suggest that egg was responsible for the deterioration of expansion of chou crust. It was also clarified that the quality of chou crust could be judged by measuring the hardness and adhesiveness of CP, because a correlation between the ratio of height to diameter and form of chou crust and hardness or adhesiveness, was observed.

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The influences of α-amylase on the expansion of chou crust were investigated. At first, adding 10.521.0 u. of α-amylase/10g of wheat starch to starch paste resulted in the improvment of expansion of chou crust. However, the addition of 105 u. of α-amylase/10g induced the worse quality compared to the one without α-amylase. Secondly, each 10% wheat starch, solution was reacted with 0,10.5,21.0,105.0 or 210.0 u. of α-amylase/10g, and lyophilized. A powder of partly digested starch was obtained. Egg and shortening were mixed with 50% of each powder solution and corresponding chou pastes were prepared. Then, the effects of reducing starch molecule weight on the expansion of chou crust were examined.
An improvement of the expansion of the chou crust was observed by using powder obtained from the digestion of starch with 10.5 u. of α-amylase/10g. However, the reaction of starch with 105.0 or 210.0 u. of α-amylase/10g induced deterioration of expansion compared to the one without adding α-amylase. Finally, the addition of AgNO₃ as an inhibitor of α-amylase to egg depressed the deterioration of expansion in the chou crust of stored chou paste. These results suggest that the reduction of starch molecule by α-amylase in eggs is one of the causes of the deterioration of chou crust derived from chou paste which was preserved under the condition of high temperature for a long period.

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Heat induced properties of whole fresh potatoes with skin cooked in Thermal Cooking Pot (T. C. POT) was compared with that cooked in ordinary pot (POT).
The cohesiveness, gelatinization, SEM and sensory evaluation results of fresh potatoes cooked in T. C. POT were comparable with those of fresh potatoes cooked in POT.
After fresh potatoes were stored at 4°C for 2,4,6 and 8 months, the properties of those cooked in T. C. POT were compared with those cooked in POT.
The weight loss was 98.15% for the 4 months and 78.90% for the 8 months stored potatoes, and the water volume was 79.52% and 69.70%, respectively.
The hardness and cohesiveness of cooked potatoes stored for 4 months were higher than those of cooked fresh potatoes (p<0.01), and cell membrane of the former was thinner. The hardness of stored potatoes cooked in T. C. POT was higher than that cooked in POT.
The cell membrane of potatoes stored for 8 months and cooked in T. C. POT were loose compared with those cooked in POT.

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A collaborative study was designed to examine the applicability of a sensory test which determines the life span of frying oil. Soybean oil (500g) was heated at 170°C for 8 hours a day using an electric fryer. Six types (pork fillet, chicken fillet, sardine, Spanish mackerel, sweet pepper or potato) of foods (50g) were deep fat-fried every 4 hours. Frying was continued until the flavor score dropped to 3, which was defined as the rancid point of frying oil. Anicidine value, carbonyl value, acid value and tocopherol content of the rancid frying oil were also determined.
The life spans of the frying oils to reach the flavor score to 3 were shorter in meat or fish frying than vegetable frying. The life spans were not significantly different among pork, chicken and fishes in spite of the marked differences in their polyunsaturated fatty acid contents. The chemical scores of rancid oils were similar among all frying oils used for different foods. These results suggest that meats and fishes promote the organoleptic deterioration of frying oils more rapidly than vegetables. The examination of the flavor score of frying oil was suggested to be useful to determine the life span of frying oil.

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Few papers have reported on the phenolic compounds in Azuki beans. In addition, these data can not be compared with each other because the extraction methods used in these studies are quite different. Therefore, we conducted comparative studies to find out the suitable method for extracting phenolic compounds with methanol qauntitatively from seed coats and cotyledons of the beans. The differences of content within seed coats and cotyledons were also studied. The results obatained were summarized as follows;
1. The most suitable extraction from seed coats was obtained with 50% aqueous methanol at 90°C for 30 minutes with three replications. The contents of each compound were estimated at 17.0 mg D-catechin equivalent/g beans for phenolic compounds,6.68 mg/g beans for chlorogenic acid and 17.3Absorbance at 540 nm in 10ml of n-Butanol: conc HCl (5: 1) solution/g beans for proanthocyanidin, respectively.
2. The most suitable extraction from cotyledons was obtained with 70% aqeuous methanol at 90°C for 30 minutes with the same replications as seed coats. The contents of each compound were estimated at 2.05 mg D-catechin equivalent/g beans for phenolic compounds,0.367mg/g beans for chlorogenic acid and 0.213 Absorbance at 540nm in 10ml of n-Butanol: conc HCl (5: 1) solution/g beans for proanthocyanidin, respectively.
3. The percentages of soluble proanthocyanidins in cotyledons at extraction temperatures of 25°C and 90°C were very low compared with those of seed coats, and lowered slightly at extraction temperature of 90°C. It was suggested from the data obtained that proanthocyanidins reacted with the proteins in the cotyledon, and formed insoluble complexes during extraction.
4. It was found that 89% of the phenolic compound,94.8% of the chlorogenic acid and 96.8% of the proantocyanidins in the whole bean were contained in the seed coats, but very low in cotyledons.
5. The above results provide very useful information for chemical investigations of phenolic compounds and for understanding the mechanism of Ann particle formation in Azuki beans.

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The preparative method of chou paste (CP) for depressing the activity of amylase in yolk, which was responsible for the deterioration of the expansion in chou crust, was examined. The beaten egg solution was added to the heated mixture including water, shortening and wheat flour, to make CP. When the temperature of the mixture became 75°C, the beaten egg solution was mixed to depress the activity of α-amylase in the yolk by high temperature. But, the deterioration of expansion in chou crust by preserving CP at 20°C could not be depressed significantly. The addition of yolk to the mixture at 75°C also gave the same result. However, the addition of yolk heated at 65°C for 30 min and fresh egg white to the mixture at 45°C remarkably prevented the deterioration of expansion in chou crust by preserving chou paste at 20°C. It was also clarified that amylase in yolk was inactivated by this treatment.

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Activities of ascorbate oxidase (EC 1.10.3.3, AAO) of 22 fresh vegetables including leafy, stalk, root and fruit vegetables were assayed. AAO activity was the highest in cucumber and pumpkin fruits (39-50 unit/g) followed by carrot roots, young ginger tubers and seedlings or sprouts (more than 1.5unit/g). There was no correlation between AAO activity and vitamin C content of fresh vegetables. Optimum pHs of AAO of fresh vegetables ranged from 5.15 to 6.50. AAO activity of all vegetables assayed was inhibited by citrate and the degree of the inhibition varied among vegetables. AAO are specifically localized in the part of fresh vegetables, and not uniformly distributed. The activities of basal part of carrot roots, celery stalks and middle part of cucumber fruits were higher than those of other parts. Although AAO activites of carrot roots and cucumber fruits decreased, those of radish seedlings and celery stalks increased during storage in arefrigerator (4°C).

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