Effect of the browning reaction products of polyphenolic compounds in the presence of polyphenol oxidase on trypsin activity was investigated. The browning reaction solution of catechol and polyphenol oxidase systems was inhibited the trypsin activity. The dialyzable components and the non-dialyzable components of the browning reaction solution was inhibited trypsin activity respectively, the latter exhibited more inhibitory effect on trypsin than the former.
The browning reaction solution was fractionated into two pigments having the reducing properties by the gel filtration on a Sephadex G-25 and G-100, and the high molecular pigments showed more inhibitory effect on trypsin activity than the low molecular pigments. A characteristic absorption maximum in the absorption spectra was not observed on the high molecular pigments, the lower molecular pigments showed an absorption maximum at 285 nm. Both pigments showed a fluorescence maximum at Ex 285 nm and Em 350 nm in a fluorescence spectra.

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The pressure cooker has been used often at home cooking because of the economy of fuel and time. In order to compare the usage of pressure cooker and steam kettle, custard pudding was chosen as a trial purpose, because of the difficulty in controlling the cooking temperature. Observation was carried out for the relation between quality of pudding and speed of heating. The texture of product was tested by sensory and objective methods.
Results are as follows ;
1. Generally, custard pudding or thick cream soup should be cooked slowly at low temperature, but the experiment assured that good results were obtained by heating short time at high temperature using any kitchen utensils or any source of heat.
2. Comparing the pressure cooker and steam kettle, there are no difference in high heating, while for low heating, the speed of rising temperature must be slow in using pressure cooker. Therefore, there are no special meaning to use pressure cooker for some food like egg protein which curdles easily below 100°C.

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Physical properties of noodles which were hand-made in the traditional method were studied from the cooking point of view.
Two types of dough containing 45% and 37% water respectively. The latter percentage is nearly the same as the noodle made by machine. The percentages of salt added were 0, 2, 4, 6, 8 and 10% of the flour in weight. Elasticity, stability, extensibility, resistance and gluten formation were compared and organoleptic evalution was made concurrently.
The dough containing 45% water and 4% salt was especially good in extendability and also better than others in most of characters mentioned above.
It seemed that the higher water content and the appropriate-content of salt are important factors of good flavor of hand mixing noodles.

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The relationship between saltiness and bitterness of some foods was studied by organoleptic tests on the water solutions of caffein and sodium chloride concentrations of which were equal to the foods.
The saltiness of sodium chloride was reduced by the addition of caffein, independent of the concentration of caffein.
The bitterness was reduced by the addition of sodium chloride.

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In many instances a food stuff has both sweet and sour tastes and proper combination of sweetness and sourness is one of the factors in making the taste good.
An experimental study has been carried out to find out the relationship between sweetness and sourness in a food stuff.
The results of the experiments are as follows :
Sweetness became less by the addition of only a small amount of acetic acid, and the rate of the sweetness lessened was directly proportional to the amount of acetic acid added.
Sourness became less by the addition of sucrose. The rate of the sourness lessened was not directly proportional to the sucrose added, but it seemed that the rate of sourness lessened was in proportion to pH of the acetic acid solution. Namely, acetic acid solutions stronger than 0.3% in concentration were not masked by adding even a large amount of sucrose.

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Sterilization commonly used in hospitals for formula milk has been steam heating at 100°C. We compared the effectiveness of sterilization between the microwave heating process and the regular steam heating process.
(1) The sample was prepared by the suspension of modified milk powder as usual. No bacteria was isolated from the milk prepared by four commercial brands of milk powder sterilized by either the microwave or steam heating process, and held in an electric refrigerator at 5°C for 24 hours.
(2) Each sample was inoculated with each one species of microorganisms as follows ; E. coli, St. faecalis, L. thermophilus, Staphy. aureus, Bac. subtilis and Sacch. cerevisiae.
The microwave heating process was effective for sterilization the inoculated microorganisms except spore-forming bacteria, Bac. subtilis.
(3) The amount of milk adhered to the bottle wall by microwave heating process was more abundant than that by steam heating process.

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Theaflavin (TF) and thearubigin (TR) have generally been known as the colored components in the black tea infusion. Particularly, thearubigin deepens the color in the infusion but its chemical structure is yet unknown.
The teas are known to be better in quality when their color is bright reddish, and a considerable amount of chlorophylls has been detected from the dry leaves of Darjeeling black tea of higher grades whose flavor is excellent.
From the results of experiments on the correlation between the period of fermentation of black tea and the chlorophylls content in the dry leaves, the flavor was proved to be excellent when the period of fermentation was relatively shorter, whereas the color was deep reddish when the period of fermentation was relatively longer.
It was recognized that chlorophylls were decomposed in proportion to an increase of fermentation periods, and that the color of black tea became more deep when the fermentation lasted for a period of two hours.
Also, High Speed Liquid Chromatography was to be effective procedure to identify of chlorophylls and its related in the tea leaves.

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The effects of tannin on the properties of gelatin jelly were investigated. The addition of tannic acid to gelatin sol at pH 3-6 has similar effects on the gelation of gelatin sol as the addition of fruits juice, coffee or black tea. The results obtained are as follows.
1) When gelation sol was added to tannic acid and adjusted to pH 5, the turbidity of sol was increased, and gelation was inhibited. But the gel formation of gelatin sol containing 10 mg% tannic acid at pH 3 and 6 or 100 mg% tannic acid at pH 6 was more faster than the sol which contains no tannic acid.
2) By warming and mixing the gelatin sol well, part of the precipitation by tannic acid was dissolved and gel formation was less inhibited.
3) As the gelatin sol added to apple juice or coffee was near to pH 5, inhibitory effect of tannin on gel formation was observed. Gelatin sol added to black tea, however, was easy to gelatinize, probably because it was near to pH 6 and contained less amount of tannin.

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The dispersing property of “roux” into milk was studied and rheological properties of white sauce were also investigated by the Haake Rotovisco RV 3. When heating temperature of “roux” was changed in the range of 40-180°C, the “roux” showed satisfactory dispersion at 120°C. For the preparation of white sauce, when the “roux” was heated at 120°C, the best way was to mix milk at 60°C with “roux” at 80-30°C. The flow curve of white sauce showed thixotropic plastic-fluid behavior, thus yield stress and thixotropic property were evaluated. The rigidity of white sauce was determined from the curve of shear stress with time under constant shear rate. By extrapolating the peak stress and the asymptotic stress to zero shear rate, the yield stress of white sauce was also measured. Power law's constants on the viscosity of white sauce were obtained through the relationship between shear stress and shear rate.

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For the purpose of planning girls' clothes, longitudinal physical growth of 40 girls born in 1948 and 1949 were studied for 9 years after their entrance to primary school. The main results are :
1. Treating longitudinally the data, the peak velocity is 8.7 cm at age 11.30 in stature, 5.4 cm at age 11.03 in lower limb length, and 4.1 cm at age 11.45 in upper limb length. The sequence of the maximum adolescent growth spurt of these items is lower limb length at first, stature and upper limb length.
2. Comparing with the cross-sectionally treated results of the same group, the greater velocity per year at peak is obtained in the longitudinally treated results. The differences are 2.0 cm in stature, 1.3 cm in lower limb length and 1.1 cm in upper limb length.
3. The average age of menarche is 11.26 for 38 girls, i. e. 1.38 year later the age at peak velocity of stature.

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Recently most salaried husbands have two days off a week or every other week. Accordingly their leisure time is increasing.
The way of living or the way of using spaces in the house is influenced by how the family spends holidays ; especially, husband's way of living is an influential factor. His way of living has been becoming largely different from that of the past. This is way the authors started this investigation and the purpose of this survey is to find out how husbands live the spaces in their house.
The work has led the following results :
1. It has been made known that about 50% of salaried men have a day off a week, 20% of them have two days off every other week, and 10% of them have two days off each week. Most of them never sacrifice their holidays, but spend their leisure time at home or have intentions to stay home.
2. Although many husbands spend holidays playing with their children or watching TV programs, those who have two days off a week sometimes go out for sports or for visits. For them the most common way of spending holidays is going out one day and having rest at home on the other day.
3. Through the observation of husbands' time allocation at home on holidays, it has been found out that they spend most of the time in a living room which is located next to a dining-kitchen and is used by family members in common.
4. As for the husbands who live in 2-DK type apartment, 8% of them have their own room. This percentage rises to 40% in the case of those who live in 3-DK type apartment. However in general it is still quite hard to allot a room to the husband living in such a limited space as a house of Japan Housing Corporation.
5. Few husbands who live in 2-DK apartment have desire for a room of their own. This apparently shows that they realize it is physically impossible to have one and they have given up such a desire.

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