The preparation of main protein fraction from soybean seeds during the development and the effect of protease in the fractions on the gel electrophoretical behavior were studied. The protein fraction, which was soluble in 40% saturation of ammonium sulfate and salted out in the 100% saturation, was prepared from aqueous extract by ammonium sulfate fractionation. The protease activity, of which maximum value was observed at pH5.9 and 7.7, in the protein fraction decreased during development of seeds. By standing the protein fraction at 20 and 30°C the number of electrophoretical bands increased, and the bands corresponding to the initial proteins in the previous report was detected. The protease was inactivated by heating(100°C, 10min)or by treatment with guanidine HCl greater than 5M. On gel electrophoresis, the products from the protein frac tion by protease in 8M urea, 1% SDS and below 5M guanidine corresponded to the initial protein in the previous report.

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The deterioration of icing cream kept in the dark was dependent largely on the hydrolysis, and the oxidative deterioration was negligibly small. The hydrolytic deterioration resulting in a rancid odor and an increase of acid value was accelerated by adding egg white, but it was effectively inhibited by the addition of ethanol within 1% of the final concentration.
On the irradiation with fluorescent lamps, photooxidation of icing cream occurred predominantly giving unpleasant off-flavor followed by an increase of peroxide value.
Egg white acted more effectively as an inhibitor of the photo-oxidative deterioration of icing cream than antioxidants such as tocopherols and lecithin, suggesting that it may intercept to pass fluorescent light through icing cream.

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Behavior of O/W emulsions which were formed by stirring 17.5% protein-water dispersion with soybean oil were studied, and the following results were obtained;
1. Any emulsions were not formed at isoelectric region of the proteins.
2. Native proteins showed much higher emulsifying capacity than that of heat-denatured proteins throughout pH range. Emulsifying capacity of the denatured proteins, however, increased 2-3 times by addition of NaCl or sucrose.
3. Effect of protein denaturation on emulsion stability appeared most remarkably when emulsions were frozen after being heated, and native proteins exhibited higher stability than that of heat-denatured proteins throughout pH range.
4. Emulsion stability was not generally affected by addition of NaCl or sucrose except the case of native proteins at neutral pH where emulsion stability for freezing was considerably improved by addition of sucrose.
5. Physical nature of emulsions generally showed sticky paste. After being heated at 90°C, however, these sticky pastes turned to weak or brittle gels in acidic and neutral pH range, and also turned to fairly tough gels in alkaline range.

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his study was conducted to ascertain whether the formation of volatile esters in banana fruit would be a reverse reaction of esterase or a coenzyme dependent reaction. Esterase activity during ripening of banana fruit became higher with the increase of esterification of added alcohol and acid to banana slices. Esterase activity was, however, observed in green banana pulp, and vascular tissues from banana pulp had fairly high capacity of esterification of added alcohol and acid, whereas esterase activity in the tissue was very low. Furthermore p-nitrophenyl phenyl-phosphonothionate(EPN), inhibitor of esterase, almost completely inhibited esterase activity from vascular tissue of banana pulp with low concentration, but the esterification in the tissue was not inhibited in the same concentrations.
Acetyl CoA and butyl alcohol changed to butyl acetate with very high extent in homogenate of pulp at over ripe stage. Acetyl CoA also made acetate ester in homogenate of mesocarp cells and in that of vascular tissue more distinctly. Homogenates and mesocarp cells could only produce acetate esters in the presence of acetyl CoA instead of acetic acid. Experiment with inhibitors also emphasized that acyl CoA is the real intermediate of esters of banana aroma.

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Anthocyanin pigment contents in three strains(A, B and C)of wild grapes in Tokachi district and Seibel No.13053 grapes were respectively 71.9, 37.4, 97.8 and 64.3mg per 100g of fresh weight in terms of delphinidin-3-monoglucoside.
From these grapes, 12 anthocyanins were isolated and identified as follows: 3-monoglucosides and 3, 5-diglucosides of delphinidin, petunidin, malvidin and peonidin; delphinidin-3-monoglucoside and -3, 5-diglucoside acylated with p-coumaric acid; peonidin-3, 5-diglucoside and malvidin-3-monoglucoside acylated with p-coumaric acid.
The species of wild grapes are discussed from the viewpoint of these pigment patterns mentioned above.

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A simple quantitative determination of allyl isothiocyanate in the hydrolysates from mustard flour, horseradish flour, and Japanese horseradish('Wasabi')powder was attempted by head-space technique.
n-Propanol was used as an internal standard. When 20ml of 0.5 volume % n-propanol was added in the experimental sample, relation curves between A'I/A'_std(A'_I and A'_std are peak areas based on allyl isothiocyanate and n-propanol in the experimental solution)and weight of sample estimated almost linear at within 0.5g of above mentioned three samples, respectively. Therefore, allyl isothiocyanate content could be calculated from following equation.
Allyl isothiocynate content, mg/100g
=(A'_I/A'_std)×{(C'_std)/(A_I/A_std)×(C_std/C_I)}×f
Where A_I and A_std are peak areas of allyl isothiocyanate and n-propanol in the standard solution, C'_std is concentration of n-propanol(ml×0.965/100ml)in the experimental solution, C_I and C_std are concentrations of allyl isothiocyanate(ml×1.020/100ml)and n-propanol(ml×0.965/100ml)in the standard solution, and f is dilution ratio of sample.
Contents of allyl isothiocyanate from mustard flour, horseradish flour, and 'Wasabi' powder hydrolysates were between 713.8 to 1, 008.0mg/100g, and these contents could not be distinguishedin the three samples.

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Edible Burdock remarkablly discolors after slicing or steeping. Discoloration was estimated by a colorimeter to indicate the results by CIE notation. Bleaching for 30min in water protected the burdock from discoloration, resulting in the slow decrease of Y(%). In addition, the change of x and y during steeping or soaking was also very low.

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In order to establish the better manufacturing method, effects of blanching, brining method and storing temperature on the qualities of salted bamboos were investigated and the following results were obtained.
1) The qualities of the bamboos salted without blanching were inferior to those of the bamboos salted after blanching in the color and the odor.
2) The qualities of the bamboos salted by brining method for long periods over than 4 months were considered to be inferior to those of the bamboos salted by sprinkling method, especially in the odor.
3) During brine storage of bamboos under low temperature, their colors looked whitish or lightgrey and their odors were grassy-smelling.

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A simple discriminative method of vegetable protein products(vp)added to commercial ground meat was developed.
The method is based on the differences of ratios of starch content to total sugar content between the alkali and alcohl extractable polysaccharides of soy protein products(sp)and of wheat protein products(wp), and also the differences of total sugar content between textured sp(tsp)and fibered sp(fsp).
Sp had lower value of starch content/total sugar ratio than wp, and tsp had higher value of total sugar content than fsp.
The discrimination of vp in commercial ground meat(25% of vp being added)can be made by the following relation for their extracted polysaccharides.
starch content/total sugar ratio; sp<0.16<wp
total sugar content; tsp>0.75%>fsp.

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