Presence of tocopherols in milk is not only biologically important as vitamin E but also is considered to have some relationship with oxidative stability of milk or milk products. The authors have developed the method of separation and determination of tocopherols suitable for analysis of animal foods as milk fat shaving relatively low content of tocopherols and high contents of interfering materials with the reaction, such as cholesterol, vitamin A and carotene in the unsaponifiable matter. Using this methad, the contents and distribution of tocopherols in milk have been made clear and antioxidant effects of tocopherols have been studies.
In this review, the contents and distribution of tocopherols in natural products, the relationships between oxidized flavor of milk and tocopherols, the antioxidant effect of tocopherols to milk fat and the synergistic effect of a few compounds to the antioxidant effect of tocopherols are discussed, comparing the results of the authors with those of former references.

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Potato or sweet potato was fried at 120, 140, 160 and 180°Cfor 1 to 3 minutes with soybean oil or lard of different stages of thermally oxidation, respectively.
When the frying period was short (1 minute), the higher the degree of rancidity was, the lower the degree of gelatinization of these fried foods, while this period was much longer (3 minutes), the difference of the gelatinization between fresh and oxidized oils was not so distinctive. The reason of this phenomenon was considered from the view point of the thermal conductivity.

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Content of sodium chloride in foodstuff and salted foods after various treatments is smaller by approximately 5 to 30% when calculated from chlorine content than from sodium content. One of the reasons for this discrepancy was assumed to be the possibility of chlorine to bind with denatured proteins and vegetable oils, while sodium does not do so. This fact was proved by experiments using radioactive sodium.

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A paper sheet (25 X 75mm, 0.01mm thick) was dipped into liquid smoke for 30 minutes. By this treatment, the paper contained 105mg of liquid smoke and, after air-dried, 3.2mg of dry matter of liquid smoke were adsorbed. When fried foodstuffs were stored in a nylon-cellophane bag, this antioxidative paper was also enclosed in the bag, and the antioxidative effect was observed.
Both papers of liquid smoke and air-dried liquid smoke showed some antioxidative activity, and, as phenol, o-cresol, p-cresol, m-cresol, guaiacol, 2, 4-xylenol, 3, 5-xylenol and 2, 6-dimethoxy phenol were detected as the antioxidative components of the liquid smoke, these compounds would act as the antioxidant while the storage of these foodstuffs.

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Natto, is one of the characteristic foods in Japan made from soy-bean by fermentation. The chief bacterium is Bacillus natto, and the chief change which takes place in soy-bean during fermentation is degradation of protein. In order to make clear the change of protein in this processing the following experiments were made.
1. Three kinds of natto were prepared using three different strains of Bacillus natto, and similarly liquid natto was made from steamed soy-bean fermented under airation and crushing. In the fermentation, total N on dry basis increased, but after 18 hrs it decreased in a small quantity.
2. Water soluble N, TCA soluble N, amino-N and peptide-N were measured about the raw soy-bean, steamed soy-bean, natto prepared with two strains of Bacillus natto and commercial natto. Water soluble N decreased very largely in steamed soy-bean, but in natto it increased to 85% of raw soy-bean. TCA soluble N, amino-N and peptide-N increased largely in natto and their proportions differed each other in the cases of two strains of Bacillus natto.

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Considerations about similarities and dissimilarities of amino acid patterns of 152 Japanese foods observed numericaly in the amino acid pattern similarity table were described. A table of foods in pattern similarity order and a table of mean values of pattern similarity between 16 food groups were prepared. Among 16 food groups, following 7 groups, namely, eggs, pulses, milks, fishes, shellfishes and cereals are considered to have definite amino acid pattern distribution, and following 8 groups, namely, potatoes, seeds and nuts, molluscs in sea, vegetables, fruits, fungi, sea weeds and others are considered to have difused amino acid pattern distribution.

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We have reported in the previous paper the metabolic changes in rats fed an amino acid diet depleted by one of the following essential amino acid, threonine, tryptophan, or phenylalanine. Similar experiments with rats force-fed a complete amino acid diet, lysine-free or methionine-free amino acid diet were conducted to observe changes in the urinary nitrogen and N'-methyl-nicotinamide (MNA), the liver tryptophan pyrrolase (TPase), tyrosine-α-ketoglutarate transaminase (TKase) activities, and the liver fat of the experimental rats 3 hours after the feeding on 5th day.
The results were similar with those obtained in the previous report that the urinary nitrogen and MNA, and the liver TPase and TKase activities of rats force-fed the lysine-free or methionine-free diet were higher than those of rats fed the complete amino acid diet.
However, it was indicated that differences between the values in all items of the lysine-free diet group and those of the complete amino acid diet group were lesser than differences in the previous experiments between the threonine-, tryptophan- or phenylalanine-free diet group and its control group fed the complete amino acid diet. This may be due to the specificity of the lysine metabolism. On the other hand, it was shown that the metabolic changes of rats fed the methionine-free diet were also specific and the changes were greater than those in the other groups.

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Estimation of five procedures to prepare κ-casein from acid casein of bovine milk was made by criterion of purity using Sephadex gel filtration and starch gel electrophoresis. There was no significant difference as to its yield among the five procedures, by which 2-3 grams of κ-casein were obtained from 43 grams of acid casein. But, κ-casein prepared using calcium-ethanol method described by Mckenjie and Wake or Sephadex method described by Yaguchi et al. was found to be highly pure. It was also proved that it was possible to prepare reasonably pure κ-casein using trichloroacetic acid method described by Swaisgood and Brunner when it was followed by Sephadex column chromatography, or using urea-sulfuric acid method described by Zittle and Custer when temperature condition was strictly controlled at the precipitation step of κ-casein by ammonium acetate.

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Nitrate and nitrite contents of spinach were analyzed about three positions; a middle part of leaf blade, a middle part of petiole, and a basal part of petiole including stem. Their changes in contents and to nitrite during storage, without and with cooking, were observed in relation to film-packing methods and storage temperatures. Their contents in canned spinach for baby food were also analyzed.
1) Nitrate content varied markedly among individual plants and positions in a plant. The highest content was found in middle-petiole, and the lowest in basal petiole.
2) No change of nitrate and nitrite contents in raw spinach was found during storage, but rapid increase of nitrite occurred in slight-decayed materials which had been stored at 20°C for 10 days in sealed palyethylene bags.
3) In cooked spinach, nitrite was detected after 4 days in storage at 6°C, and nitrate decreased coincidently.
4) In canned spinach, the content of nitrate did not show any change at all tested storage-temperatures.
5) When the spinach was boiled in water for 3-10minutes, 55.7-73.5per cent of nitrate were removed in the water, and with subsequent washing for 10minutes more 9.7-16.5per cent were removed.

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The purpose of this paper is concerned with the effects of the difference in essential fatty acid (EFA) configuration of the dietary fats on the functioning and lipid composition of the hepatic mitochondria. The dietary fats, which contained similar amount (approximately 53%) of EFA but differed in its configuration on the triglyceride molecule, were prepared from the commercial soy bean oil and the lard from a pig fed on a high safflower oil ration. These fats were administered to weanling male rats at 5% level (w/w) at the presence or in absence of cholesterol (1%).
When cholesterol was not included in the diets, the extent of mitochondrial swelling was similar between the two fats. Addition of cholesterol resulted in general in a decrease of the swelling rate and this phenomenon was most prominent in the rats fed the lard for 6 weeks.
Fatty acid composition of the mitochondrial phospholipids was substantially identical in 6 weekfeeding experiments. The composition at 13 week-feeding was, however, significantly different between the two fats. Thus, soy bean oil group contained, in terms of percentage composition, more palmitic and less arachidonic acids than the lard group. Although addition of cholesterol to the diets resulted in a decrease in palmitic, stearic and arachidonic acids and an increase in linoleic acid, no difference was observed between the two fats.
Concentration of phospholipids and cholesterol of hepatic mitochondria from rats reared for 13 weeks was not different between the two dietary fats. Addition of cholesterol caused in an increase in the concentration of cholesterol, but there was no difference regardless of the dietary fats examined.
These results suggest that, when cholesterol was ingested simultaneously, the difference in the glyceride structure of dietary fat influences the composition of phospholipids in the hepatic mitochondria and probably their structure, and this in tern causes the change in the membranous function of the mitochondria.

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A large proportion of fresh foods, particularly vegetables and fruits, are served intact on the table. Accordingly, such foods are in danger of being polluted by foreign matters which are far from edible, such as microbes present in the soil during cultivation, dust, earth, fertilizers, pesticides, bactericides, fungicides, and so on.
The authors attempted to utilize the supersonic washing procedure, which had been already used as washing machine and instrument to eliminate those pollutants.
As the preliminary study, experiments were done to investigate the effects of irradiation of supersonic waves on the destruction of vitamine, such as B₁ and C, which are existing in the tissues, and as the result, it was reported that very little effect was produced by supersonic irradiation on those vitamins.
The subsequent study reported herein deals with the effects of the irradiation of supersonic waves (frequency: 20 kilocycles) on the removal of Cu²⁺ of copper-containing pesticides contaminated to several kinds of vegetables and fruits. The results are as follows.
It was ascertained that marketed fresh parsleys, strawberries, lettuces, and grapes contained 10, 1.8, 3.8, 3.5γ of Cu2+ per gram, respectively. On the other hand, if the Bordeaux mixture had been employed for them, it were found that these vegetables contained 3200, 66, 1080 and 340γ of Cu²⁺ per gram, respectively.
By manual washing, about 30% of copper were eliminated after one minute washing, and even after the 15 minutes treatment, this value was risen only to about 40%. On the contrary, by the supersonic washing, it was found that 60% of the ion were washed off in a minute and over 90% in ten minutes.
In conclusion, it has been verified that the irradiation of supersonic waves on vegetables and fruits is extremely effective for the elimination of the residual Cu²⁺.
There remains the danger, however, that the improper processing conditions may lead to the destruction of vegetable tissue cells, marring the external appearance of plant and debasing their value as food. In the ranges of this experimental conditions it was also confirmed that the effect produced by supersonic washing procedure for the first one minute, cannot be heightened even if the processing time is extended to 10 or 15 minutes, for the quantity of copper ions eliminated by this method is not in proportion to the duration of irradiation. The danger involved in prolonged treatment with supersonic wave is that tissue cells may be disintegrated by excessively long processing.

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