Effects of commercial soybean lecithin (SPC) on the various properties of oil used for pan-frying were tested. SPC was added to a corn oil in the range of 0.25-3.0%. These oils were tested using an apparatus designed as a model of pan-frying. SPC markedly influenced the changes in various properties of oil during pan-frying. The following results were obtained.
1. Waving motion of oil surface: When corn oil was heated over 180°C in a state of thin film, unevenness of the oil surface occurred. That is, Concavo-Convex was formed on the surface of the oil. This phenomenon was described as “waving motion of oil surface”, and was effectivelly prevented by the addition of SPC.
2. Deterioration of oil: When SPC was added to corn oil in the range of 0.5-1.0%, thermal oxidative deterioration measured by peroxide or total carbonyl values was effectively prevented. However, the presence of SPC over 1% caused a great increase of browning in heated oil.
3. Heat adhesion of protein food: When corn oil was heated over 160°C at the state of thin film, heat adhesion of chicken meat to the pan surface occurred. But this phenomenon was effectively prevented by the addition of SPC.
4. Foaming tendency: When SPC was added to corn oil over 1%, a remarkable foaming was observed during the cooking of chicken meat.

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Erythritol is a kind of tetrahydric sugar alcohol, has low calory and does not induce tooth decay. In our previous paper, the characteristics of sweetness of erythritol and other sweeteners were compared with those of sucrose by sensory test. The characteristics of sweetness of erythritol were similar to those of sucrose. When erythritol was used together with aspartame, the characteristics of sweetness were the closest to those of sucrose.
In this paper, we examined the characteristics of sweetness of different mixture ratio of erythritol and sucrose by sensory test. In addition, taste preferences of erythritol in several cookings were compared with those of sucrose by ranking test.
Results obtained were as follows:
1. Sample 1 (sweet rate of erythritol was 25%, i. e.25% of total sweetness was provided by erythritol, the rest by sucrose) was preferred to sample 4 (sweet rate of erythritol was 100%) in terms of astringency and overall significantly. However, no significant difference was observed among sample 1-4 in terms of other items.
2. The taste preference by ranking test showed no significant difference among samples when erythritol was used in lemon squash and jelly.
3. On the other hand, ice cream containing erythritol as a only sweetener was not preferred significantly in terms of aftertaste and overall.
4. It was not useful to substitute erythritol for sucrose in mizuyokan whose sucrose content was very high.
5. Shiruko whose sweet rate of erythritol was 40% was poor in aftertaste and was not preferred.
6. As a result of several test cookings with low sweetness, erythritol was possible to be used in place of sucrose.

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In order to examine oxidative deterioration of lipids mackerels during heating in a microwave oven, broiling and boiling, POV, COV, fluorescence intensity, browning degree, and fatty acid composition in the extracted lipid were determined.
The results obtained were as follows;
(1) The oxidative deterioration of lipids in fish meat cooked for the optimal time (2 min and 30sec for a microwave oven,10 min for broiling and 15 min for boiling), was slightly lower for fish heated in the microwave oven than for fish heated in any of the other ways.
(2) When heated fish was stored for 6 days in the refrigerator, although the browning degsee of lipids in fish meat did not change significantly, the POV, COV, and fluorescence intensity all gradually increased. The largest increase was observed in the lipids of fish meat heated in the microwave oven.
(3) When the fish meat was reheated in the microwave oven after having been stored in the refrigerator for two days, the largest increase of the value determined was observed in the lipids of fish meat first heated in the microwave oven.

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“Geppei” is a traditional Chinese food. A way of preparing “Geppei” is as follows: First of all, the mixture of sugar, water and vinegar is boiled until the sugar content becomes 67%. This sugar solution is used after aging for several weeks. Then, the sugar solution, lard, wheat flour, and “kan-sui”, which is a Chinese special alkaline solution, are kneaded to a dough. Bean paste wrapped in the dough is baked into “Geppei”. A characteristic of the crust of “Geppei” is that it retains its soft texture during several weeks storage. In this study, the effects of the vinegar in the sugar solution on the physical properties of the crust were studied.
The crust made of the sugar solution with the vinegar was softer than the crust without vinegar. Invert sugar was produced markedly in the sugar solution with the vinegar during boiling or aging. The crusts were made using the sugar solution which contains sucrose, glucose and fructose in various ratio, and the breaking strength was measured by a Rheoner. The more the glucose and fructose was included, the smaller the breaking strength and the softer the crust was. This is thought to be due to high hygroscopic property of invert sugar. In addition, the effect of “kan-sui” was to make the crust a desirable brown color.

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The effects of seasonings (soy sauce, white miso and red miso) and subsidiary materials (umeboshi, ginger and sea tangle) on the oxidation of lipids in boiled sardine fillets were investigated. Lipid oxidation was evaluated by determining with the peroxide and carbonyl values, fluorescence intensity and coloring degree.
Boiled fish with miso or soy sauce showed preventive effects on the oxidation of lipids during storage in a refrigerator. And the bolied fish with mixtures of ginger and miso showed a greater preventive effect than that with miso alone. On the other hand, sea tangle apparently promoted the oxidation of lipids in fish boiled with miso or soy sauce.

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Carrots were cooked in a conventional cooker, a pressure cooker and a microwave oven. Viscosity and pH of the carrot extracts were measured.
Water soluble pectin was extracted from the carrot and then alcohol-insoluble substances (AIS) were taken from it. The contents of galacturonic acid and methoxyl group in AIS were measured, and the properties of pectin jelly made from AIS were examined.
The results obtained were as follows:
1) Viscosity of the carrot extract cooked in a microwave oven was a little higher than that obtained by other methods.
2) The pectin jelly became increasingly hard in a conventional cooker, a pressure cooker and a microwave oven, and got softer with an increase of cooking time.
3) The amount of galacturonic acid which was soluble in the carrot extract increased along with a lengthening of cooking time.
4) The amount of methoxyl group in pectin which was soluble in the carrot extract decreased with a lengthening of cooknig time.
5) The amount of methoxyl group correlated with the hardness of pectin jelly.

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To determine the relationship between taste awareness for saltiness or sweetness and preference for foods having salty or sweet taste, a survey was carried out to three groups of 226 students classified according to food education and sex. The students were female majoring in home economics, female and male in other courses. Data were analyzed statistically. The results are summarized as follows:
1) Students studying home economics preferred less salty taste and foods compared to the other female and male students. Female students were aware of less sensitivity to both tastes, and preferred less salty taste and sweeter foods than male students.
2) In all groups, there was a significant positive correlation between favorite seasonings with salt and salty food preferences. That is, the students who liked salty food preferred stronger salty taste. The same was also noted in regard to sweetness.
3) Among two female students groups, there was a significant negative correlation between taste awareness of sensitivity to saltiness and favorite seasoning with salt, and also between taste awareness of sensitivity to saltiness and salty food preferences. That is, student with greater awareness of sensitivity to saltiness, preferred less salty taste and foods, the same tendency also being noted for sweetness in the other female students.

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