Atomic absorption spectroscopy was applied to the determination of magnesium in food.
1) Absorbance at 285.2mμ was selected for magnesium.
2) Linear relationships between absorbance and concentration were found over 0-1.0 ppm of magnesium.
3) Sample was laid in ashes in an electric muffle furnace at 550°C, and after the ash was dissolved with hydrochloric acid and made up to 100ml with water, the solution was used for analysis of magnesium.
Silicate and aluminium interfered remarkably with magnesium determination and other metals interfered feebly, but the interferences were eliminated by adding excess amount of strontium chloride (Figs. 3, 4). Recoveries of added magnesium were satisfactory, and the observed values by atomic absorption spectroscopy agreed with those obtained by EDTA titration method. (Tables 1, 2).
4) Reproducibility of analytical values was satisfactory. Coefficient of variation was 3.3 percent for magnesium (Table 4).
5) Contents of magnesium in marine products were about 300-660ppm. (Table 3).

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Investigations on the physico-chemical properties with special reference to the stability were carried out with lenthionine, a substance which was isolated from dried Shiitake mushroom.
Lenthionine is practically insoluble in water but soluble in non-polar solvents. Lenthionine in crystalline form can be stored unchanged for several months. However, the stability in an aqueous solution is greatly affected by the pH of the solution. It is fairly stable in the range of pH 2 to 4, but, in solutions above pH 5, it is decomposed quite rapidly.
The stability of lenthionine was not affected in the presence of oxygen, salts and surface active agents. On the other hand, the decomposition of lenthionine was accelerated by light and reducing agents, such as cysteine or sodium pyrosulfite.
Heat decomposition products of lenthionine in the buffer solution were hydrogen sulfide and thiocarbonyl compound.

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Studies were carried out on the sensory properties of lenthionine with reference to its application to foods with the following results;
1) The aroma of lenthionine is identified as that of Shiitake.
2) The threshold values of lenthionine in water and in edible vegetable oil were 0.27-0.53ppm and 12.5-25ppm, respectively.
3) The addition of 1-20ppm of lenthionine to several foods demonstrated that it gives Shiitakelike flavor to foods and makes them palatable.

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The consumption of dry seasoned noodle in Japan has been increased. The fat absorbed in noodle, however, is considered to be oxidized during storage in markets, and such oxidized fat taken in digestive organs is perhaps disagreeing with them, since thermally oxidized fat was indigestible and plant oil was remarkably oxidized by the storage at 30°C for several months.
This study was performed to clarify the denaturation of the noodle fat. Two of dry seasoned noodles were stored at 30°C for 30 and 70 days, respectively. A dry seasoned noodle which was fried with lard containing 20% corn oil was prepared and stored at 30°C for 70 days, The extracted fats from all noodles were tested for their denaturation.
In one noodle on the market, peroxide value and dimer content of fat were not so much increased after the storage at 30°C for 70 days, but, in the other noodle on the market, peroxide value and dimer content were increased considerably after the storage at 30°C for 30 days. Plant oil was detected in the latter noodle by gaschromatographic analysis, The fat from the noodle which authors prepared by frying with lard and corn oil was oxidized considerably after the storage at 30°C for 70 days.

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The nutritive value of diets for patients in 137 cases was investigated.
(1) Some essential amino acids (EAA) were deficient in 21 cases which were supplied with less than 0.79g of protein per Kg body weight per day.
(2) All EAA was sufficient in amount in 82 cases to which were given more than 1.10g of protein per Kg per day.
(3) 16 cases with some EAA deficiency and 18 cases without any EAA deficiency were seen for groups between 0.80 and 1.09g of protein per Kg per day.
Two different cases in the third groups could not be differentiated with sole values of “Protein Score” by FAO ('57) or “Egg A/E Ratio” “E/T” by FAO/WHO ('65). But the values of “Protein g/Kg×Egg A/E Ratio” and “EAA mg/Kg×Egg AIE Ratio” could be divided into two different cases which explain the results in the third groups.

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The carbohydrates in the powdered leaves of Artemisica Capillaris were divided into ten fractions, and free sugars and the component sugars of each fraction have been investigated mainly by the method of paper chromatography. The following results were obtained.
Glucose, fructose and sucrose were found as free sugars from the hot 80% methanol soluble fraction.
Glucose, galacturonic acid, arabinose and xylose were detected as small molecular pectin from the hot 50% methanol soluble fraction.
Galacturonic acid, galactose, arabinose and xylose were detected as soluble pectin from the fraction soluble in cold water.
Galacturonic acid, galactose, mannose, xylose, rhamnose, glucose and fructose were detected as hot water-soluble polysaccharides from the hot water-soluble fraction.
Galacturonic acid, galactose, arabinose and xylose were detected as protopectin from the 0.5% ammonium oxalate soluble fraction.
Galactose and xylose were detected as the component sugars of hemicellulose from the fraction soluble in cold or hot 5% NaOH.
Galactose, fructose and xylose were found as component sugars of β-cellulose or γ-cellulose, from the fraction soluble in cold 20% NaOH.
Only glucose, galactose and xylose were detected as the component sugars of α-cellulose from the fraction soluble in hot 5% H₂SO₄.

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The powdered leaves of Artemisica Capillaris were extracted with ether, and then holocellulose was prepared by treatment with 0.5% ammonium oxalate or hot water.
From the fraction soluble in 5% NaOH, hemicellulose A, hemicellulose B, and hemicellulose C were separated by the Norris-Preece's method, and the yield of hemicellulose A was 8.23%, of hemicellulose B 0.50%, and of hemicellulose C 0.36%.
The quantitative analysis of the sugar components indicated that these hemicelluloses had only two components, xylose and galactose, and the molecular ratio between these two sugars was 4.13: 1 in hemicellulose A, 4.09: 1 in hemicellulose B, and 4.12: 1 in hemicellulose C.

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The first suggestion of protein-magnesium relationship was made by Colby et al. (1951). Menaker (1954) and Bunce et al. (1963) elaborated thereafter on this problem.
The following study was designed to give further information on the influence of dietary protein and magnesium levels on the calcium and phosphorus metabolism, using 30 male albino rats of the Wistar strain, averaging 41g in the initial body weight.
Either in the low or high protein intake, there was no difference in the weight gain between the diet with 50mg% and that with 200mg% of magnesium. In moderate protein intake, however, the gain with low magnesium intake was greater than that with high magnesium diet.
In the group receiving equal amount of protein, the calcium metabolism was not affected by dietary magnesium level but the lower level of magnesium caused higher absorption and urinary excretion of phosphorus. The high protein-low magnesium diet caused a decrease in absorption of magnesium.
In the group receiving equal amount of magnesium, the protein-deficient diet decreased the percentage absorption of calcium and phosphorus, and increased the percentage excretion of calcium in urine.

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The amount of hydrogen sulfide as well as that of volatile basic nitrogen was rapidly increased at high temperature. In case of the storage at low temperature, no positive correlation was recognized between the freshness and the amount of hydrogen sulfide, but, in case of the storage at higher temperature, it was clearly recognized. That is, the amount of hydrogen sulfide was increased in proportion to the increase of volatile basic nitrogen.
The estimation of the fish freshness by hydrogen sulfide value is useful, since it shows the beginning stage of decomposition when the fish contains about 50γ percent of hydrogen sulfide.

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The present paper deals with the changes in contents of organic acids in homogenized or intact baby clams during storage at 5°C.
1. In case of the homogenized storage, succinic acid, fumaric acid, lactic acid, acetic acid, oxalic acid and malic acid in muscle were increased in proportion to the increase of storage period, but the other acids showed little changes. In viscera, however, lactic acid was increased in proportion to the increase of storage period, but the other acids were decreased on the second day of storage. (Tables 1, and 2)
2. When a baby clam is living, it retained about 80 percent of total acids in viscera and about 20 percent of total acids in tissue. (Tables 1, and 2)
3. In case of the intact storage, fumaric acid was increased in proportion to the increase of storage period, but the other acids showed little changes. (Table 3)

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Analysis for ⁹⁰Sr and ¹³⁷Cs was carried out on soybean and its products (soybean paste, fermented bean, bean curd, etc.) which were produced during 1961 through 1963. Content of those nuclides in soybean reflected the geographlcal difference of radioactive fallout deposition to a considerable extent. ⁹⁰Sr content did not change substantially during this period in spite of the remarkable increase of fallout rate in 1963, while ¹³⁷Cs content showed clear increasing tendency from 1962 to 1963 because of its larger dependency upon current fallout rate than ⁹⁰Sr. ⁹⁰Sr concentration relative to calcium (pCi/gCa) in soybean curd was remarkably lower than in any other foods of plant origin.

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When rice is used as a sole source of protein in otherwise complete diet, there is an accumulation of liver fat. However, the substitution of this by wheat does not increase the level of liver fat above the normal range. This difference has been attributed to the difference of amino acid composition of proteins of the two cereals, whereas the contents of lysine and threonine are almost the same in both diets. In contrast to the above fact, an appreciable accumulation of liver fat was observed when animals were fed on diet containing an amino acid mixture simulating the composition of wheat protein and potato starch-sucrose mixture. Furthermore, the supplementation of amino acids to rice diet to meet the amino acid content of wheat diet or a simple adjustment of nitrogen content of rice diet to that of wheat diet did not prevent the fat accumulation. Decrease of nitrogen content of wheat diet by the dilution with starch also did not increase the liver fat. These results threw a question that some factor (s) other than amino acid composition may be important for the regulation of liver fat content of rats on cereal diets.

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Le gluten s'obtient par malaxage d'un paton de farine sous un mince filet d'eau. Il a des propriétés de cohésion, d'elasticité et d'extensibilité á l'état hydrate qui lui font une place unique parmi les proteines végétales. on sait que la qualité du solvant a de I'influence sur les propriétés du gluten et sur son taux d'extraction.
J'ai d'abord tenté de préciser les caractères physico-chimiques des proteins du gluten obtenues par extraction avec ces différentes solutions (l'eau distillée, une solution de NaCl 0.5 M et le tampon phosphate), par la filtration sur gel de dextrane et le comportment électrophorétique en gel d'amidon des suspensions dans l'acide acétique N/100 des glutens. En meme temps, j'ai essayé de voir l'influence des milieux d'extraction sur l'indice alvéographique.

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Depuis l'ètude par Osborne (1907) de la classification et des caractères des protéines du blé, de nombreux chercheurs ont abordé cette étude, principalement au cours des 20 dernières années; le matériel protéique s'est révelé extrêmement complexe. J'ai tentè prèciser les caractdrès des protéines de la farine et du gluten séparés par fractionnement selon la methode d'Osborne-Feillet.
Après l'éxtraction, j'ai dosé l'azote sur chaque fraction, et précisé les caractères physico-chimiques par la chromatographie sur Sephadex et le comportement électrophorétique en gel d'amidon.
Mon travail a permis de préciser nos connaissances sur la biochimie et la physico-chimie des protéines de la farine et du gluten.
La chromatographie sur Sephadex et l'électrophorèse ont permis de preciser l'hétérogénéité des protéines ainsi isolées. J'ai obtenu une solubilisation de 4 à 8% des protéines du gluten dans NaCl 0.5M.

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Although detailed information on the behavior of ATP and related substances in freeze-dried foods is limited, the results of the author's experiments on the muscles of scallop, surfclam, and abalone have revealed that ATP and its related substances in these muscles are mostly fixed in the dehydrated state for 5 months, but when the products are softened with water for 1-10 minutes, the ATP is almost completely decomposed, resulting in the accumulation of AMP. It has been also found that the water-holding capacity of abalone muscle is inferior to that of scallop and surfclam.

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The stability of vitamin C for ultraviolet ray radiation was measured on L-ascorbic acid (AsA) crystal and aqueous solutions of AsA (5-50mg%) and of dehydroascorbic acid (DAsA) (20mg%). The results were compared with those by the radiation of visible rays.
1) AsA crystal was almost inactive for either radiation.
2) AsA in aqueous solution was remarkably decomposed by the ultraviolet rays. This fact was to be taken to suggest that the decomposition of vitamin C might be caused by the relieving of double bond in the vitamin C's endiol radical, which was done by the ultraviolet rays. The effect of the rays depends on the time of radiation, distance between the light source and materials, the concentration of AsA in solution, and the shallowness of the solution.
3) AsA in aqueous solution was slightly affected by the visible rays.
4) DAsA in aqueous solution was even stabler than AsA in aqueous solution. DAsA was only slightly affected by ultraviolet rays.

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In an attempt to clarify the reason why the basal metabolism (B.M.) presents a seasonal variation among Japanese, B.M. was measured monthly throughout a year with Canadian missionaries who are living in a church in Kyoto, and whose house's climate is similar to the Japanese house's.
Results obtained are as follows;
1) B.M. of the Canadian did not show any consistent seasonal variation, while the seasonal variation was verified to be significant among Japanese.
2) Studies on factors affecting seasonal variation of B.M. of Japanese revealed that physique and constitution (endocrine activity) of subject, quality and quantity of diet taken, and seasonal pattern of physical activity have important bearings with the seasonal variation of B.M.
3) Among those factors mentioned above, Canadian have much larger physique, high thyroid activity, large dietary intake, especially high fat intake, and high muscular activity in summer, as compared with Japanese.
4) Above mentioned factors may compose a multifactor complex affecting B.M. to inhibit its seasonal variation which is to be initiated by physiological adaptation to the severe seasonal change of climate.

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Using a basal diet containing an amino acid mixture simulating the composition of polished rice protein, the effect of amino acid supplementation on growth of rat was studied to explore the difference between the actual effect of supplementation of amino acid to rice diet and the theoretical expectation. When the basal diet contained 6% of amino acid mixture simulating rice protein, single supplementation of 0.4% of L-Lys did not stimulate the growth of rat but the supplementation of L-Lys together with 0.24% of DL-Thr improved greatly the growth just like the case of amino acid supplementation to the natural rice diet. This result may imply the importance of the interrelationships between dietary Lys and Thr in addition to the availability of Thr in rice protein provided the diet containing an amino acid mixture can neglect the problem of digestion of amino acids in food protein. When the level of amino acid mixture in basal diet was increased to 8%, however, significant improvement of growth was observed with single supplementation of Lys. Some problems relating to the basic principles of amino acid supplementation are also discussed.

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