Attempts were made to obtain some indications as to safe use of frying oils through analysis of volatile products, in view of recent findings on the presence of toxic components in excessively heat treated oils as well as in their volatile products. Soybean oil was heated intermittently at 180°C up to 30 hrs by frying potato, chicken meat, soybean curd, whale meat, mackeral, green pepper, and moist cotton balls (a control system) controlling water depletion from each food item. Oil samples thus prepared were distilled under a stream of nitrogen directly into carbon disulfide and their concentrates were analyzed by GC and GC-MS.
No distinct differences among the oil samples were observed by GC, such as number of peaks observed and their relative amounts. Among low boiling fractions were detected alkanals, caproic acid, 1-octane-3-ol and those high boiling fractions decanal, decadienal, and 7-phenyl-heptanoic acid, one considered to be toxic. There appeared to be decrease in amounts of low boiling fractions accompanied by increase in those of high boiling fraction by increasing heating time. TLC analysis (benzene-hexane-acetic acid 70 : 30 : 2) of the total volatile fraction gave 3 spots and the one near Rf 0.4 was found to contain the phenyl compound mentioned above and showed the most strong absorbance at 278 nm.

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Histological changes of mackerel bones were observed in canning process. Cooking of mackerels by boiling the cans at 116°C for 60 minutes proved most effective to soften the bones causing the collagen fibers in the bone matrix to be gelatinous : bone lacunae disappeared or became obscure to discern. Gelatinized collagen fibers became stained weaker with eosin (hematoxylin-eosin stain), anilline blue (Crossman stain), acid fuchsin (van Gieson stain) and by acrolein-Schiff reaction, while they became stained much stronger by periodic acid-Schiff reaction and with alcian blue. The amount of calcium in mackerel bones showed little changes in canning process.
Form the results above, it may be concluded that the softening of fish bones is caused not by the decrease of calcium in the bones but by gelatinization of collagen fibers and release of calcium from collagen fibers.

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The texture of the fronds of wakame (Undaria pinnatifida) was evaluated by means of both mechanical (curd meter, Ho Denki Co.) and sensory tests. The tensile strength of these specimens was found to be from 20 × 10⁴ to 70 × 10⁴ dyne/cm², and the hardness was found to be 20 × 10⁴ to 85× 10⁴ dyne/cm². The simple correlation coefficient was 0.66 for the correlation between the sensory evaluation of the texture and the values of tensile strength, and was 0.23 for the correlation between sensory evaluation and hardness.
Water insoluble-alginate, -Ca and -Mg were significantly correlated with tensile strength and these simple correlation coefficients were 0. 86, 0. 76 and 0. 87, respectively, but those were not correlated with hardness.
The conclusion drawn from these experiments was that the texture of wakame fronds might be represented by tensile strength, and the toughness of wakame fronds was dependent on the water insoluble-alginate, -Ca and -Mg contents.

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The factors for softening or hardening of cooked wakame (Undaria pinnatifida) fronds were elucidated. The results obtained were as follows :
1) The wakame fronds became extremely soft by boiling for 15 minutes. However, the insoluble alginate content, the metal (Na, K, Mg and Ca) contents and the patterns of DEAE Sephadex column chromatograms of the alginate did not change after boiling. The viscosity of sodium alginate solution heated in boiling water for 15 minutes significantly fell than that before heating.
2) It was observed that a treatment with 5% acetic acid for 15 minutes led to harden the fronds followed by the increase of insoluble alginate and the considerable decrease of metals (Na, K, Mg and Ca).
From these results, it was concluded that the wakame fronds were rendered soft by some changes in the dispersion state of alginate molecules of the fronds by boiling, and that the hardening of the fronds treated with acetic acid would be induced from the increase of insoluble alginate which might be the result of the formation of free alginic acid due to liberation of metals by means of treatment with acetic acid.

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Experiments were carried out to study the easiness of removal of boiled egg shells, and effects of storage time, alkaline treatments, acid treatments and cleaning the cuticle on it were investigated.
Removing shells of boiled new-laid eggs was fairly difficult but it became easier after holding new-laid eggs for about forty-eight hours.
Among the alkaline treatments, ammonia gas treatment was most effective to remove the boiled egg shells.
Removal of egg shells became difficult, when pH value of egg white was decreased by treatments of hydrogen chloride, carbon dioxide and acetic acid gas.
As to the color, hardness and water holding capacity of boiled egg white, the evident difference was seen between the new-laid eggs and the alkaline treated ones.

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When the refrigeration of dough was applied in the processing of bread, effects of yeast, sugar and ethyl alcohol contents and also the mixing condition of dough on the quality of bread were investigated.
In the case of 9% yeast content, the CO₂ production and the bread volume were lowered by the storage of dough at 4°C for two days or more. The more the yeast content was, the lower the tolerance for fermentation.
As to the sugar content, when this was 11%, the bread volume was relatively constant before seven days' storage in cold, while this was 3%, the bread volume could keep constant only three days' storage and the storage of moreover affected severely the volume and this was decreased.
By the addition of ethyl alcohol of over 1% to dough, the dough expansion and the CO₂ production were influenced, this addition showed a negative effect on the fermentation of dough.
An insufficient mixing reacted as a negative factor on the fermentation and the bread volume was decreased.
Thus, it was assumed that, for the prevention of the drop of fermentation tolerance induced by the refrigeration of dough, a high content of sugar in dough would be effective.

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It has been found that determination of the formaldehyde with acetyl aceton can be carried out by heating sample-reagent mixture for 5 minutes at 60°C followed by cooling with running water for 1-2 minutes. This method is very speedy relative to the conventional method which includes 30 minute-incubation at 40°C and another 30 minute-standing at room temperature.
Values obtained by the new procedure satisfactorily correlates with those by the conventional process.
The positive error in the present method caused by methylol compounds contained in the extracts is less than that observed after 30 minute-incubation at 40°C in the conventional method.
It has also been found that 2-3% of dimedone solution is required for the complete removal of formaldehyde if the concentration is more than 1 ppm.

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The purpose of this study was to investigate the calibration method of the pressure transducer on the human body surface concerning with such setting methods as fixed by tape (method B) and unfixed (method A), and with such setting positions as the half and the lower 1/3 part of upper arms. Subjects were 50 young females.
1) A remarkable difference in the response pressure was observed between two setting methods. In the case of the method B, the relationship between applied pressure and the response pressure was almost linear (Y=0.955 X-0.28) and the individual differences were small. In the method A, on the other hand, the response pressure increased rapidly when the pressure 5 g/cm² was applied. As a result the relation equation obtained was Y=1.008 X+ 19.69, and the individual differences were large.
2) A little difference in the response pressure was observed between two positions. The standard deviation of it obtained on the lower 1/3 part was smaller than that on the 1/2 part.
3) The correlation coefficients between regression coefficient of each subject obtained from applied-response pressure relation and each one of the following items, subcutaneous fat/upper arm girth and Rohrer index, were 0.209 and 0.034 respectively.

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In order to investigate factors influencing the degree of family-intimacy : of the aged, eighty-nine males and ninety-three females were subjected of interview. The following correlations between intimacy and several dominating factors were observed.
1. Sex : females show higher intimacy than males.
2. Age : the advancing age of females makes no difference with regards to family-intimacy. Males become alienated from family with age.
3. Matrimony : male's marital life favorably affects in terms of intimacy but female's is significantly found to be independent.
4. Working status : aged males who dominantly preside in farming show high intimacy. At the mountain village in Tohoku district where the survey was conducted, majority of breadwinners in their prime ages go out as seasonal workers away from the community. Consequently those who are left behind with advanced age have to undertake some farming.
This trend is different from that of the rice-cultivating community reported in a previous paper.

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[in Japanese]

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