Enzymatic procedure is one of the advantageous methods for the industrial production of L-amino acids. In this review, the enzymatic resolution of DL-amino acid and other enzymatic methods mainly studied by the author are described. Some of the results of the application of amino acids to foods are also discussed.

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The loss of iron while cooking was investigated with the cuisines of Japanese and European styles, according to the normal menu at the convent to which the author is belonging.
The average amounts of iron contained in the raw materials, with which these two styles of cuisines were prepared, were found to be 12.3mg per day for European and 11.7mg for Japanese, and the losses of iron while cooking were 17% for the former and 32% for the latter, respectively.
It was found that the iron content of natural foodstuffs was somewhat smaller than that cited in the Food Composition Tables, and, comparing with the Recommended Daily Dietary Allowances, the iron intake following these cuisines was found to be 23% smaller for Japanese and 1% larger for European.

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The loss of calcium while cooking was investigated with the cuisines of Japanese and European styles, according to the normal menu at the convent to which the author is belonging.
The average amount of calcium contained in the raw materials, with which these two styles of cuisines were prepared, were found to be 633 mg per day for European and 357mg for Japanese, and the losses of calcium while cooking were 5% for the former and 9% for the latter.
The calcium content of natural foodstuffs was found to be somewhat smaller than that cited in the Food Composition Tables. It was also found that only 54% of calcium were taken from Japanese cuisine as compared with the Recommended Daily Dietary Allowances, and for European cuicine, the calcium intake was sufficient.

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As the first step to get the information on the range of fat intake optimal for growing individuals, the dietary habits in relation to fat, oil, and fatty foods of 1140 nursery children of 9 areas in Japan have been surveyed in 1964.
It was found that 40-80% of these, depending upon the living status of the children took fat, oil, or fatty foods at least once a day in 4-5 days of five consective days, while about 80% of the children craved for any of these foods at same time in their past transitionally, 20-30% of the children were given butter before one year of age, other fat and oil following the butter.
The frequency of fat, oil, and fatty foods consumption appeared in their family menu did not relate neither with the height and weight, nor with the health condition of the children, but did so significantly with obesity of their family members.

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In an effort to find out whether or not the strong preference of Japanese children in nursery schools for fatty or oily foods has come from the fat poor Japanese diet, another dietary survey wa s undertaken on the American School children living in Tokyo who were supposed to be big fat consumers. The results were compared with the data on the Japanese counterparts consisting of girls in a Japanese junior high school. The same method as that used on the Japanese nursery school children was applied to both samples.
The American children's dietary record shows that a large proportion of the children has 20-40 fatty dishes in five days whereas most Japanese girls have 10-19 fatty dishes and nursery school children have 5-14 fatty dishes.
There was, however, no difference in taste for fat, oil, and fatty foods between American and Japanese children. This suggests that the following two interpretations might be possible: one is that the optimum amount of fat intake in growing and developing period is much higher than the amount which is now considered to be proper; the other is that the good flavor or consistency of fatty diet makes children crave fatty diet beyond the physiological requirement.

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In an attempt to study on metabolic changes in rats fed an amino acid diet devoid of an essential amino acid, rats were force-fed a phenylalanine-free, phenylalanine and tyrosine-free or complete amino acid diet for 4 days and killed 3 hours after the feeding on day 5. The urinary nitrogen and N'methylnicotinamide (MNA), the tryptophan pyrrolase (TPase) and tyrosine-α-ketoglutarate transaminase (TKase) activities of liver, and the fat content of liver were estimated. Beside, in order to clarify the effect of amino acid patterns of diets on the liver TPase and TKase activities, intact and adrenalectomized rats were administered a threonine-free or complete amino acid diet and sacrificed three hours later.
The results indicated that the urinary nitrogen and MNA, the TPase and TKase activities of liver, and the fat content in liver of rats fed the phenylalanine-free or phenylalanine and tyrosine-free diet were higher than those of rats fed the complete amino acid diet. Both of liver enzyme activities of adrenalectomized rats force-fed the threonine-free or complete amino acid diet were lower than those of intact rats fed the same diet respectively. Furthermore, the TPase activity of adrenalectomized rats fed the threonine-free diet was higher than that fed the complete amino acid diet, whereas, the liver TKase activities in both diet groups of adrenalectomized rats were almost the same level.
These results demonstrated that the TPase activity could be directly affected by the utilization of tryptophan in diets in this experimental condition, whereas changes in TKase activity depended on the function of adrenal gland in preference to the direct effect of amino acid patterns in diets.

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Atomic absorption spectrophotometry was applied to the determination of copper in foods.
(1) Absorbancy at 324.8mμ was measured to determine copper.
(2) A linear relationship between an absorbancy and the concentration was found within the range of 0-20p. p. m. copper.
(3) Samples were burnt to ashes in an electric furnace at 550°C, and, after the ashes were dissolved with 5ml of 6N hydrochloric acid, 5ml of calcium chloride (2, 000p. p. m. Ca) were added and made up to 50ml with water. This solution was submitted to the analysis of copper.
(4) Chromium and tin interfered with the determination of copper fairly, but the interferences were eliminated by adding excess amount of calcium.
(5) Recoveries of copper added to the sample were found to be satisfactory.
(6) The reproducibility of analytical values was also satisfactory, that is, the coefficient of variation for copper was 3.3% for green peas.
(7) Contents of copper in raw and canned foods were about 0.1-2.0mg%, and the content of it in oysters was remarkably high in comparison with other fishes.

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Atomic absorption spectrophotometry was applied to the determination of zinc in foods.
(1) Absorbancy at 213.9mμ was measured to determine zinc.
(2) A linear relationship between an absorbancy and a concentration was found within the range of 0-5 p. p. m. zinc.
(3) Samples were burnt to ashes in an electric muffle furnace at 550°C, the ashes were dissolved with 5ml of 6N hydrochloric acid and made up to 100ml with water. One ml of the acid solution was pipetted and added 5ml of 6N hydrochloric acid, 5ml of calcium chloride (2500p. p. m. Ca) and 20ml of ethylalcohol, and then made up to 100ml with water. This solution was submitted to the analysis of zinc.
(4) Silicon, tin, copper, chromium, magnesium and potassium interfered with the determination of zinc considerably, but the interferences were eliminated by adding 2500p. p. m. of calcium.
(5) Recoveries of zinc added to the sample solution were found to be satisfactory.
(6) The reproducibility of analytical values was also satisfactory, that is, the coefficient of variation for zinc was 4.83% for oyster.
(7) Contents of zinc in marine products examined were about 0.5-3mg% with the exception of oyster and crab, contents of it were50-70mg% for the former and 16mg% for the latter, respectively.

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It is well known that the occurrence and isolation of βacid in the alcoholic extract of rice-polishings “Roh-Oryzanin” have been already established by U. Suzuki in 1910. Afterwards, in 1924, the chemical constitution of the compound was confirmed to be 2, 6-dihydroxyquinoline-4-carboxylic acid by Y. Sahashi. In 1925, further biological activities were studied in his laboratory and found that there may be a certain Bios-like activity for beer yeasts while no effect on animals.
Recently, the present authors have made further investigation of the biological activities in plants and found that there may possibly be some new promoting influence against the plant-seed-germination.

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Food consumption patterns of 19 countries all over the world were studied by the calculation method about pattern of numerics developed by authors. Pattern similarity S (A, B) between pattern A (a₁, a₂…, a_n) and pattern B (b₁, b₂…, b_n), radian distance R (A, B) between pattern A and pattern B, one component (X_r) removed pattern similarity -X_rS (A, B) and angle DA (B, C) between the two directions from pattern A to pattern B and to pattern C (c₁, c₂, …, C_n) were defined as follows.
Results shows the food consumption pattern of Japan has high pattern similarities with those of Taiwan (0.971), Turkey (0.959) and Italy (0.946) and has lowest one with that of Uganda (0.486).
Food consumption patterns of 19 countries are classified into two groups. The first group includes 10 countries, mainly West Europian countries, U. S. A., Australia, U. K., Norway, West Germany, France, Italy, Spain, Brazil and Uganda. The second group includes 9 countries, mainly Asian countries, Japan, Taiwan, Philippines, Rumania, Turkey, U. A. R., Ethiopia, India and Mexico.
The pattern of Japan belongs to the second group and her position is nearest to the first group, and her pattern is becoming closer to that of Italy and further from those of Taiwan and Turkey. In recent few years, the food consumption pattern of Japan is changing in the direction with the angle of 29°05′ of the pattern of Italy and going away from the pattern of Taiwan with the angle of 27°52′.
The change of Japanese pattern from 1958 to 1964 is mainly caused by the increased consumption of vegetables and fruits, meats, eggs, and oil and fats.

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We examined the possibility of low temperature storage of cereals under-water in order to store the “reserve” rice for long periods without substantial loss of quality. The storage experiments were carried out from May 1967 at laboratory scale. Large-scale experiments are now in progress at Lake Biwa.
Packing materials for under-water storage of cereals must be: (1) Resistant to structural attack by water, (2) Resistant to physical shock, (3) Moistureproof, (4) Airproof. Conventional structure materials like metal, wood or cement are not expected to meet these requirements over a prolonged period. Plastic film recently developed for the food packing appeared to be fit for the purpose.
The mechanical intensity of several plastic films was compared and the oriented nylon film was found to be suitable as a basic component. Some other properties of the nylon film was also shown.

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It was found that nylon film shows low permiability to nitrogen, oxygen, and carbon dioxide gases, but high to water-vapor. The transmission characteristics of the film depended upon temperature and relative humidity of the environment. It is one of the feasible way to laminated nylon film to endow it with moistureproofness. Among the laminated film prepared in trial, nylon film laminated with polyethylene and either of aluminum foil or polyvinylidene chloride coated nylon film were found to be most favourable for under-water storage of cereals.
Preparation methods and properties of laminated films were shown.

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The under-water experiment of cereals storage was designed and carried out at well and pond. Practical usefullness of laminates as packing materials has been well recognized in laboratory scale experiments but not evaluated yet in a practical scale. A large-scale experiment for practical use of this new storage method was carried out at Lake Biwa over a rainy season in order to ascertain the usefullness of the packing materials and to investigate the possible changes that might occur in the cereals stored under such a closed system.
Experimental conditions, place, method, kinds of cereals, packing materials and storage system (open, air, CO₂), selected or determined in this paper were found satisfactory for the purpose.

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Preservation of commercial “instant lamen” has been studied from a practical point of view with special regard to oxidizing denaturation.
“Instant lamen” was wrapped with color cellophane (red or green) as filter and then was exposed to sunlight and fluorescent lamp.
The peroxide value of fat that was extracted with ether from the sample was measured at regular time intervals.
Consideration of the transmittance of the color cellophane in ultraviolet and visible regions and of the relative energy of sunlight and the fluorescent lamp showed that 450-550mμ and ultraviolet region near 385mμ had considerable influence on the denaturation of the lamen.
The denaturation of the lamen was also carried out about the influence of various temperatures (room temp., 30, 40 and 50°C) under sealed condition in a paste-board box-that is, in the same condition as in that of transportation and storage.
As the result, in the case of the ronm temperature and 30°C, the fat extracted did not show any great change of the peroxide value. Under conditions of 40 and 50°C, however, the peroxide value gradually increased.
As above mentioned, it has been found out that no matter how high the surrounding temperature may be, for instance, during the summer season, if the light of 450-550mμ of visible portion and ultraviolet region near 385mμ are eliminated the preservation of the “instant lamen” under vacuum, is possible without oxidizing denaturation over a period of a month.

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