The researcher previously proposed an idea based on the investigations which were tested the home managerial abilities of the present Japanese housewives (N. Sakai, 1966, 1988). This paper applies the same method as the previous works to 210 housewives who reside in Korea.
The followings are the major findings :
1) The Korean housewives are better than the Japanese housewives on the overall home managerial ability.
2) So far as the activities are concerned, the Korean housewives co-ordinate and control well, while they have poor abilities to plan and to evaluate their management. This tendency is the same as the Japanese housewives.
3) The Korean housewives skillfully manage such resources as residence, family love, the budget and assets, and their time, and they think residence more important than foods as compared with the Japanese housewives, but they are not good at managing Public facilities and home equipments : this is the same tendency as the Japanese housewives.

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The effects of texture and thickness of various foods on the masticatory movement were studied especially focusing on the time of the first bite. Masticatory movement was obtained, recording the force loaded on an artificial tooth during the time of mastication.
The masticatory movement was characterized by the following parameters : the maximum masticatory force of the first bite (F), the maximum derivative of the force of the first bite with respect to time (ID), loading time during the first bite on the tooth (t₁), the masticatory duration between the initiation of the first bite and last bite leading to swallowing (T) and the number of times of bites during the mastication (N).
F and ID were found to be independent of the thickness of foods but dependent on the changes of texture of the food by cooking, reflecting the physical properties of foods.
t1, N and T were affected both the thickness of foods and textural changes of foods by cooking. They were found to reflect not only the physical properties but also the size factor of foods.
On the other hand, the masticatory cycle (N/T) was found to be independent both the thickness and texture of foods. It may reflect a personal rhythm.

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A basic study for baking cookie was carried out. The sucrose in the formula of sugar snap cookie was replaced by lactose or sea sand. Significant changes were found in characteristics of dough and in qualities of cookie as follows :
1) Doughs with lactose or sea sand had higher consistencies than dough with sucrose.
2) Cookie dough with sucrose reached maximum expansion during 3 min in an oven and shrinked. In the other hand dough with lactose or sea sand showed continuous expansion for 4. 5 min and showed a little shrinkage.
3) In the vacuum expansion test with the samples taken out from the oven, the, dough with sucrose kept higher expansion rate for 2 min, however the dough with lactose or sea sand showed it only 30 sec and then decreased slowly.
It was found that sucrose has a great role in the specific expansion and shrinkage as well as surface crack of sugar snap cookie. We assumed that these results were caused by competition for water between flour and sucrose.

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“So, ” a kind of ancient milk product in Japan, was a food preservable at least for 4 months after manufacturing. Paying an attention to the water activity, a trial to reproduce the “So” was carried out. An isothermal-adsorption like curve was obtained from the measurements of water activity and water contents. On the basis of this results, three types of “So” were prepared as follow : S-14, concentrated to 14 % (limit of heat concentration); S-18, concentrated to 18 % (same water contents as cheese); S-16, concentrated to 16 % (intermediate between S-14 and S-18). Changes in the appearance, water activity and water contents of the samples were investigated during storage.
In the case of S-16 and S-18, the growth of molds was observed on the 10th day during storage and their water activities were 0. 90-0. 94, respectively. On the other hand, the growth of molds was not observed in the S-14 even after the storage for 1 month in the beaker. In this case, the water activity was maintained below 0. 80 and water content was a low value of 10 %. Additionally, it was possible to store S-14 sample for long times in the jar, as water activity of S-14 possessed low value (0. 65) after 4 months.
It was found from the above results that “So” could be prepared by concentrating raw milk to less than 14 % in ancient Japan which had no storage technology.

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Redox potentials of various bleaching agents and the fiber model substances were measured in order to estimate the oxidizing power of them.
Bleaching agents used were sodium hypochlorite, hydrogen peroxide, sodium percarbonate, sodium perborate and sodium hydrosulfite. On the other hand, glucose and glutathion were adopted as the model substance of cellulose and wool fibers respectively.
Results obtained were as follows.
1) The redox potential of sodium hypochlorite was higher in plus value than that of hydrogen peroxide. That is to say, the bleaching agents of perchlorite series had more intensive oxidation power than that of peroxide series.
2) Every redox potentials of peroxide bleaching agents used in these experiments were nearly equal. Sodium hydrosulfite exhibited minus potential.
3) The potential of these bleaching agents lowered with the increase of pH, with point of infection appearing in diagram.
4) The potential of glucose and glutathion were lower than that of peroxide series, and with the increas of temperature the potential of that became lower.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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