Oil solubilizing components in the nitrogenous fraction of soy sauce were investigated by adding amino acid and some peptide preparations in the standard system consisting of soy sauce powder, cottonseed oil and water.
Hardness and adhesiveness of the solubilized system were apparently promoted by amino acids possessing alkyl radicals such as Ileu, Met, Leu, Val and some peptides such as Gly-Glu and Glu-Asp.
These amino acids at 1% or higher concentration lowered the surface tension of water, which paralleled with promotion of the solubilization phenomenon in the standard system. On the otherhand, 0.03% surfactants did not promote solubilization, although they reduced effectively the surface tension of water.
These results suggested that solubilization of oil in the aqueous system containing about 70% soy sauce powder is caused by the amino acids and the peptides in the powder acting as micelles with non-nitrogenous components of soy sauce.

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Canned asparagus packed with and without inner coated tin container were stored for 12 months at room temperature. Volatile surfur compounds in head space gas of each 4 cans with 3 months intervals were analyzed by means of gas chromatography equiped with FPD detector. The results obtained were as follows:
(1) Hydrogen sulfide, carbon disulfide, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide were found as the chemical components of head space gas of the canned product packed with and without inner coated tin container.
(2) Using tin container with out inner coating resulted in reduction of hydrogen sulfide levels. Changes in carbon disulfide and methyl mercaptan concentrations were similar to those of hydrogen sulfide levels in the samples with and withont inner coated tin container. Levels of methyl mercaptan and hydrogen sulfide in sample cans were also within 2.0ppb throughout the storing period. Dimethyl sulfide level was higher than those of the other volatile sulfur compounds in all sample cans, and little changed during storage.
(3) An increase in hydrogen sulfide levels and a decrease in carbon disuifide levels were found within 20 mins after opening cans.

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Invertase was immobilized in an bead shaped polymer(0.5-1mm diameter)by radiocopolyme-rization of some synthetic monomers at the frozen temperature. Some of the basic characteristics were investigated and enzyme column was tested.
1) Immobilized invertase preparations having high retained activities(60-90%)were prepared by polymerizing some monomers without acrylamide.
2) The optimum reaction temperature was about 65°C being 5°C higher than that of the native invertase.
3) Heat stability was greatly improved. After heating at 70°C for 12min, immobilized invertase hold sti11 70% of the original activity but native one had 40%.
4) Immobilized invertase was more resistant to aniline, urea and Hg⁺⁺ but on the contrary, more sensitive to SDS, guanine and Cu⁺⁺.
5) The Km value was 2.45×10^-2 mole and 1.75×10^-2 mole for immobilized and native enzyme respectively.
6) The activation energy was increased by 0.9Kcal/mole after immobilization.
7) When used as immobilized enzyme column, it was found to be more advantageous to increase the concentration of substrate and enzyme in the entrapping polymer.
8) 30% sucrose solution was continously charged in to the column at the flow rate of SV 1. The substrate was completely decomposed up to 28 or 50 days.
9) There were no big differences on the basic characteristics between bead shaped and membranous immobilized invertase preparations except for the behavious to some inhibitors.

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Thermal conductivities of concentrated juice and its diluted one of Satsuma (Citrus unshiu Marc.) were determined by non-steady-state comparison method. As the result it was found that thermal conductivity of citrus juice was in proportion to the temperature and in reverse proportion to the concentration, and on the whole it was nearly the same with that of water.

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The invbestigations on the enzyme constituents in the commercial enzyme preparations originated from Asp. oryzae and the components in salty-red-miso prepared using only the enzyme preparations were carried out to obtain the following results.
(1) Compared with the rice-koji, enzyme preparations were low in activities of peptidases except leucine-aminopeptidase type I, and remarkable differences in the activities of peptidases were observed among the enzyme preparations.
(2) From the results of brewing trials, the degree of protein hydrolysis in enzyme-miso was recognized to be affected remarkably by the activities of peptidases in the enzyme preparations.

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