A bacterium which produced the enzyme hydrolyzing konjak was isolated and characterized. This strain was identified as Bacillus circulans. The B. circulans No. 215 grew favorably in F medium composed of konjak, sodium phosphate, magnesium sulfate and ammonium sulfate, in comparison with H medium which was only made up of konjak. The strain was able to grow in F medium in the pH range 5.5-10.5, and grew most favorably in the pH 6.0 to 9.5 region. Viscosity of F medium decreased rapidly at the initial stage of the cultivation, while reducing sugar in the culture medium was accumulated with the increase of cell population. The properties of the crude konjak-decomposing extracelluar enzyme from this strain were as follows: the optimum temperature was 30°C and the optimum pH range was between 6.4 to 7.2. The enzyme was stable for 40min at 55°C. On thin layer chromatogram of the degradation products of knojak in the culture medium, the spots of glucose, mannose and other products of knojak in the culture medium, the spots of glucose, mannose and other products were detected.

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This paper describes the changes in lipid contents and lipolytic enzyme activities in rice bran during storage at 37°C. One hundred of fresh rice bran contained 11.5m mol triacylgylcerols, 0.85m mol glycolipids, and 0.7m mol phospholipids. The lipid contents decreased during storage in the following order: phospholipids, triacylglycerols, glycolipids. The presence of phospholipase C and phospholipase D other than lipase and phospholipid acyl-hydrolase was confirmed in rice bran. The ratio of the activities of these lipolytic enzymes was as follows; lipase: phospholipid acyl-hydrolase: phospholipase C: phospholipase D=100:24:35:39. They retained 30-60% of the activities after 60 days starage.

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The constituent of moisture, protein, fat, ash, fiber, total sugar, reducing sugar, saccharose, starch, peroxide value and thiobarbituric acid value were determined as chemical constituents in 25 kinds of commercial cooked Curry and sensory test on 14 kinds commercial cooked Curry was also carried out. On results of chemical constituents analysis, characteristics of Curry was examined by application of principal component analysis. The results were as follows: (1) The analytical value were ranged from 65.7-80.0% for moisture, 3.3-5.6% for protein, 4.4-13.6% for fat, 1.1-2.8% for ash, 1.1-4.0% for fiber, 5.9-15.8% for total sugar, 0.4-1.6% for reducing sugar, 0.8-4.3% for saccharose, 2.7-10.4% for starch, 1.9-5.9 for peroxide value, 0.3-1.1 for thiobarbituric acid value. (2) Principal component analysis showed that component of carbohydrate and moisture was first principal component and component of quality indication of fat and sweet taste were second principal components. (3) By a sensory test it was found hat weak aroma of spices and meat, and weak brown colour, tasty, and balanced taste were favoured.

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The fatty acid components and free fatty acid were determined in 23 kinds of commercial cooked Curry. On results of fatty acid components analysis, characteristics of Curry was examined by application of principal component analysis. The results were as follows: (1) The fatty acids were existed in all samples analysed, the average of which was 1.4% for lauric acid, 2.6% for myristic acid, 23.8% for palmitic acid, 2.7% for palmitoleic acid, 10.3% for stearic acid, 44.4% for oleic acid, 11.3% for linolic acid, 1.4% for linolenic acid and 2.3% for unknown, respectiuely. (2) Principal component analysis showed that lauric acid was first principal component, and linolic acid was second principal component. (3) The free fatty acids were existed in all samples analysed, the average of which was 8.0mg/100g for lauric acid, 7.6mg/100g for myristic acid, 25.0mg/100g for palmitic acid, 2.0mg/100g for palmitoleic acid, 6.5mg/100g for stearic acid, 40.2mg/100g for oleic acid, 20.2mg/100g for linolic acid, 1.8mg/100g for linolenic acid and 1.6mg/100g for unknown, res- pectively. (4) By comparing the pattern of fatty acids on total and free form, it was shown that the acid whose contents was large in total was easy to be free.

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The new protein hydrolyzed seasoning (mixed seasoning) was prepared from the mixture of defatted soy bean and dried bonito after hot water extraction. The aroma compounds were isolated by reduced steam distillation and head space vapor collecting method followed by the identification of these compounds using GC and GC-MS. These results were compared to those of krill hydrolyzed seasoning (krill seasnoning) obtained under the same experimental conditions. The aroma concentrate consisted of acids, pyrazines, lactones, furans, sulfur containing compounds, pyrroles and aldehydes. These constituents were almost same in those of the two seasonings, however, Aldol type condensates Such as 2-phenyl-2-butenal, 4-methyl-2-phenyl-2-pentenal and 5-methyl-2-phenyl-2-hexenol were not found in the mixed seasoning in spite that they are characteristic compounds in the aroma of the krill seasoning. The light acceptable shoyu-like flavor of the mixed seasoning is discussed from comparison of constituents of aroma concentrates and head space vapors to those of krill seasoning.

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The clarification of apple juice has been studied by using two kinds of endo-polygalacturonase (PG) and two kinds of exo-PG produced by Aspergillus nigre and one kind of pectinesterase (PE) produced by Asp. oryzae. Every one of these pectolytic enzymes by itself could not clarify apple juice. The clarification of apple juice was only accomplished by the joint action of endo-PG I and PE I, and a mixture of endo-PG II or either of exo-PGs had no activity for apple juice even in the presence of PE I. Both endo- and exo-PGs were extremely adsorbed onto protopectin. Exo-PGs had weak activity to digest protopectin, whereas endo-PG II was inferior to endo-PG I in digesting protopectin.

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Catalase was immobilized on acid clay using ethylsilicate. The relative activity of the immobilized catalase to the free enzyme was 23% upon a reaction for 5min at pH 7.0, 25°C in a batchwise reactor. The treatment of waste water containing 3.6mM H₂O₂ at 25°C through a column with 2.0g of the immobilized catalase continuously degraded 85% of the hydrogen peroxide in 3000ml of the waste water.

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The temperature correction and the check system of the conductometric flow injection analysis for measuring the salt content in food were proposed. The temperature dependences were approximated by linearity at 5°C interval around the center temperature of 20°C, and the resulting slopes (dC/dt) of the straight lines were calculated. The temperature coefficients were defined as the quotients where dC/dt where devided by observed conductivities (C_s) at standard temperature (T_s: nearer temperature to 20°C in each temperature section).
Temperature coefficient, α=dC/(C_s dt)
One can calculate the conductivity (C_t) at an arbitrary temperature (t) within each temperature section by following equation.
C_t=C_s{1+(t-T_s)α_n}
where, α_n means the temperature coefficient of the specific temperature section to which t belongs.
The availability of this correction method was evaluated under different temperatures and resulted in good agreement with biases less than 0.2% (w/w) designated as NaCl.

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