In order to evaluate the flavour quality of canned peaches, the aroma of canned peaches produced from six cultivars was investigated, preliminarily. Volatile components of canned peaches were concentrated by lyophilization followed by solvent extraction of the distillates and were examined by GLC, GC-MS and silicagel colum chromatography respectively. About 75 to 80 components were resolved and there was no difference among cultivars, qualitatively. 28 components were estimated or identified by mass spectrometry, as well as comparison of GLC retention data with known compounds. The identified components were γC₆-γC₁₀, δC₁₀, γC₁₂ Iactones, benzaldehyde, heptadecane, benzylalcohol, βionone. Percentage of these lactones in canned peach volatile amount to 31.9-53.2%. Therefore, lactones would be useful to evaluate the quality of canned peach on aroma. On aromatic aldehydes which extracted directly from syrup with diethyl ether, six spots were detected on PPC and one of them was identified as vanillin.

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A design of conductance cell intended for practical determination of organic acid content in food by means of the method based on conductometry is described.
1) A simple dipping cell with bright platinum plates as electrodes was manufactured and characterized electrochemically.
2) The estimated admittance and the reciprocal of the solution resistance completely coincided for 10^-3 to 10^-4N potassium chloride and/or the 30O times diluted solutions prepared from the sample solutions containing O.3 to 2.5% organic acid as citric acid.
3) A linear relation was obtained between the conductance measured by the cell and the organic acid content titrated with standard sodium hydroxide solution: correlation coefficient, r=0.998 and standard deviation, S_y·x=0.045.
4) An advanced cell was devised and the cell constant(θ)was 1.221cm^-1 in the range of 10^-3 to 10^-4N potassium chloride; hence, a 300 times diluted solution of 0.1N potassium chloride was adopted as the standard solution for calibration(3.33×10^-4N, K=49.40μΩ^-1cm^-1 at 25°C).
5) The response time of the advanced cell was nearly zero and there was no change of themeasured value for 30 minutes successive run.

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The trypsin inhibitor of Japanese soybean(Onihadakazaki No.1)were separated by DEAE-cellulose chromatography and the major fractions were fractionated by isoelectric forcusing chromatography. Heat-inactivation of the fractionated inhibitor was also conducted. The results were as follows.
(1) Trypsin inhibitor activities were separated into five fractions(F-1-F-5)on DEAE-cellulose collumn and ratio of their activities was F-1 8.7%, F-2 9.3%, F-3 26.9%, F-4 10.1%, F-5 45.0%, respectively.
(2) The major trypsin inhibitor fractions(F-3, F-4 and F-5)on DEAE-cellulos ecolumn were further fractionated by isoelectric forcusing chromatography. F-3 fraction was separated into two components, pI of those was 3.80 and 4.20, respectively. pI of F-4 fraction was 4.20, and F-5 fraction was separated into two components(pI 4.20 and 5.00).
(3) Five trypsin inhibitors by DEAE-cellulose chromatography were determined heat-inactivation. F-2, F-3 and F-4 fractions showed about 90% remaining activities, and F-1, F-2 fractions showed 60-70% remaining activities at 100°C for 20min. F-2 and F-4 fractions still had about 35% remaining activities at 120°C for 20min. It seems that these trypsin inhibitor fractions had strong thermal stability.

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Micelle formation of soy sauce extract in the aqueous solution and its model system was investigated by the viscosity method and dye solubilization method.
Log ηr(relative viscosity)vs. c(concentration)curve of the solution of soy sauce powder sharply changed in the slope of the line at the concentration of 35% w/w, which coincided with the point where a sudden increase was observed in the amount of p-dimethylaminoazobenzene (DMAB)solubilized in the solution.
The model solution containing saccharose and polypeptone remarkably solubilized DMAB under specific conditions, and synergistic effect of the two components on solubilization of DMAB was also observed.
These results suggested that the solubilization phenomenon by soy sauce extract is based on the micelle formation of the solution with surface-active nitrogenous components and some carbohydrates in soy sauce.

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The flux and the loss of colorant which were supposed to be important factors in commercial application of ultrafiltration(UF)for improvement of the quality of ammonia-caramel color were basically examined. Caramel solutions(3.5-21.0%)were ultrafiltrated in a stirred batch cell equipped with PM-10 membrane at 20-40°C at 4kg/cmcm². From the linear relations between the flux and the logarithm of initial concentration, it was found that this UF system was well represented by a known equation: J_W=k₃·ln(C_g/C_B). Based on the values of C_g and k₃ obtained, any flux under arbitrary conditions can be estimated. The use of 20/100 dilution of caramel color was most effective in the flux at every temperature. UF of 20/100 dilution to the 5-fold concentration factor at 40°C resulted in a 4.88% loss of colorant, 3.75(ml/cmcm²· hr)of flux and 60% removal of imidazoles. The loss of colorant was highly dependent on temperature and concentration factor. A linear relationship between the logarithm of the loss and the initial concentration makes it possible to estimate the loss in UF of various caramel solutions. Both the loss and the flux can be applied to the UF of caramel colors having a similar relation between viscosity and solid content to that of the caramel color tested.

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In order to study the interaction between muscle structural protein and soybean protein, myosin B and CIF were employed. The forming ability of aggregate and gel by heat-treatment was examined under limited conditions.
The following results were obtained.
1) Under the lower protein concentration, the degree of aggregate formation of myosin B and of its mixture with CIF was decreased with rising of the pH, while that of CIF was increased to maximal extent in the range of pH6.5-8.5 by heating of 100°C. Furthermore, it was suggested that CIF conjectured some structural transitions of moleculess with heat treatment at pH6.0 and 100°C. The aggregate formation of CIF seemed to be inhibited in the presence of myosin B at pH6.5-9.0 and 100°C heat treatment.
2) Under the higher protein concentration, the interaction of myosin B with CIF was recognized at all the pH used in this experiment when heated at either 60°C or 100°C. Thus it was concluded that the gel formation was improved and accelerated when the both proteins were present in the higher protein concentration in the system.
The stable and rigid gel was formed by heating at 100°C for 30min under existence of 50mg/ml CIF and 15mg/ml myosin B. This effect was remarkable at pH7.0 and 8.0 than atpH6.0.

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A convenient clean-up method for determination of vanillin in sugars was developed.
This method is based on the formation of NaHSO₃-vanillin complex. After decomposition of the complex with sulfuric acid, vanillin was extracted with benzene and subjected to GLC analysis.

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