Several amines have been found in some kinds of Miso in the course of this series of study. Therefore, 147 samples of homemade Miso were collected from farm households in Saitama, Tochigi and Gunma prefectures and analyzed for histamine in order to get more detailed information about their qualities.
All the samples were treated with acidic alcohol. Histamine in the extracts was detected qualitatively by paper chromatography and after purification, identified in the form of its picrate, by the melting point determination method with authentic substances. Quantitative determinations of histamine in the extracts were made by paper chromatographical and photometrical procedures. The results are as follows.
The histamine content in the sampled Miso was in a range of zero to 28 mg% and approximately 6 % of the total samples were found to contain histamine in an amount higher than 20 mg%. However, there existed no significant correlation between the histamine content and other individual factors such as duration of aging and compositions of ingredients including sodium chloride.

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The present studies were conducted in an attempt to investigate the tyramine content in relation to the general qualities including chemical composition and redox potential (Eh) value of Miso and acid-base titration curve of its extract. The following results were obtained. (1) Miso containing tyramine in large quantities had a tendency to be of high moisture and low salt. (2) There were considerable differences in slope of acid-base titration curve of the extract among the three kinds of samples, that is, ordinary, vegetables preserved, and calcium carbonate fortified samples of Miso. Tyramine was observed to have an increasing tendency in the case of this curve showing a gentle slope. (3) The Eh value of Miso was found to vary greatly from sample to sample, especially depending upon the conditions with or without preserved vegetables. In general, Eh value was higher in the bottom part than in the top part even within the same cask. However, there was no significant correlation between the tyramine content and the Eh value under the present experimental conditions.

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Young yellowtail was cultivated for one year, feeding three types of feed mixed with powdered oil, white fish meal and yeast (diet B-D) against raw fish (diet A) and measured its growth pattern. Fat content of flesh, liver, pyloric caeca and fatty acid composition were also examined and its effect on the feed incorporated with oil on young yellowtail was investigated.
Considering the effect of cultivation, diet B showed nearly the same result as when fed with raw fish. Fat content of flesh increased in December and decreased in February when water temperature was lower. Fat content of flesh was different, even when diet B and diet C composed of the same fat content as raw fish were fed. The weight of liver increased the mostly in December and decreased in February. Young yellowtail fed with feed without oil (diet D) showed lower fat content in the liver. Showing differences to flesh and liver, pyloric caeca increased in fat content, even in February. Fatty acid composition of fat of young yellowtail was examined. Fatty acid composition of fat in feed was apparently transferred almost completely to flesh, liver and pyloric caeca of young yellowtail. Especially in diet B and diet C added with powdered oil, transfer of C_{18: 2} was clearly identified. Comparing the fatty acid composition of fat of young yellowtail in December and in February when fat content decreased, the composition of C_{14: 0} and C_{16: 0} showed a little variation in flesh, liver and pyloric caeca.

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Riboflavin is known to be readily destroyed by sunlight, but only recently attention has been called to the photolysis of riboflavin in milk. In order to examine effective wave length for the photolysis, liquid milk in petri-dishes covered with various light filters was exposed to white fluorescent light for 180 min and riboflavin before and after the irradiation-was fluorimetrically assayed. Riboflavin in the milk in control petri-dishes (without any filters) was lost by ca. 60 percent after the irradiation. When. blue (400-560nm), brown (mainly above 500nm) and red (above 550nm) filters were used, riboflavin losses in the same period of irradiation were about 20, 30 and 10 percent, respectively. A slight decrease in riboflavin content occurred in petri-dishes placed in the dark for 180 min. These results indicate that red-colored bottle will be the most recommendable container for protecting liquid milk from photolysis of its riboflavin.

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In order to prevent the putrefaction of boiled milled rice keeping in commercial electronic jars at various temperatures, the inhibitory activity of glycerol monocaprylate with sucrose fatty acid ester and potassium pyrophosphate, all of which are approved as the food additives, has been tested against the bacteria isolated from the putrefied rice. As a result, it was found that this composition exhibits more effective inhibition of bacterial growth than that of glycerol monocaprylate alone, and also good detergency to remove the bacteria on surfaces of the inside container in an electronic jar.
In addition, it was also verified that the composition is to be sufficient for bacteriostatic activity from the results obtained by practically using electronic jars.

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The effect of various reductones and their derivatives on glyoxalase enzyme system has been studied with crude enzyme systems extracted from ox or mouse liver, applying the semicarbazide method for the enzyme activity assay. Inhibition spectra of the two enzyme systems were not significantly different from each other. Of polyphenols, ortho- (catechol, pyrogallol), meta- (resorcinol, phloroglucinol) and para- (hydroquinone) dihydroxy derivatives exhibited strong, medium and very weak inhibitory effect respectively. Substitution at 4-position of catechol with polar groups (gallic acid, Dopa) decreased the inhibitory potency of the compounds except for chlorogenic acid. p-Benzoquinone showed markedly strong inhibition, which might be caused by direct reaction of the compound with one of the substrates, glutathione, to form some new compounds as judged from the results with UV spectrum measurement and paper chromatography. Aliphatic reductones and their related compounds (ascorbic acid, ascorbic acid-3-phosphate, dehydroascorbic acid, triose reductone, diacetyl) exhibited weak or slight inhibitions. Bidentate chelating agents, oxalate and phthalate, showed a little different effects on the two enzyme systems, though the inhibitions were not significantly strong in both cases.

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Authors studied on fluorescence of tocopherols, α-tocopherol esters and a main metabolite of α-tocopherol i. e., α-tocopherylquinone, also on interference of vitamin A, β-carotene, vitamin D, vitamin K and cholesterol on the fluorometric determination of tocopherol. A comparative study between Rindi method and fluorometric method were undertaken to estimate the tocopherol in serum of human, horse and monkey.
The results thus obtained showed good agreement with the values of Rindi method and satisfactory reproducibility with simplicity.

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