The screening tests on the myrosinase-like activity of intestinal bacteria of chickens were made employing the cultural analysis of intestinal flora.
The tests were made on 68 healthy chickens. A progoitrin prepared from rapeseed was used as substrate, and goitrin in biological fluids was assayed by the spectrophotometry.
In the chickens fed with rapeseed oil meai inactivated its myrosinase by cooking, goitrin was detected in the middle intestine, rectum, and blood.
The incubation tests indicated that the caecal contents consistently hydrolyzed progoitrin to goitrin, and the middle intestine contents and recrum contents were occasionally active. But, in those of other portions, the myrosinase-like activity could not be found.
Moreover, bacteria with myrosinase-like activity were isolated from the caecal contents and caecal feces. These may include various members of the intestinal flora, such as Catenabacterium, Bifidobacterium, Bacteroidaceae, Streptococcus, and Enterobacteriaceae.
Thus, these studies.indicated that progoitrin is hydrolyzed by living bacteria which are normal inhabitants of the lower alimentary tract in chickens.

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The Stability of enzyme in honey was investigated in a series of study on the quality of honey.
1) In the enzyme preparation were present amylase, glucose oxidase and α-glucosidase, and for each of them the optimum conditions were elucidated.
2) All of the enzymes were labile in the vicinity of pH 3.8 of honey, and amylase was relatively stable to heating.
3) The enzymic activity showed little decline on storage at cold temperature (3°C), but dropped gradually at room temperature.
In experiments on enzymic activity of honey stored in a sealed glass bottle for seven months at room temperature (20-28°C), the loss of amylase activity was least among the examined enzymes.
It was considered that the loss of enzymic activity during storage would depend on moisture content as well as pH value of honey.

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Changes in the egg white frozen at -20°C were investigated to obtain information as to the cause and mechanism of decrease in foaming power of whole egg during the freezing storage at-20°C.
The foaming power of frozen egg white blended with unfrozen yolk was lower than that of unfrozen egg white. The foaming power and foam stability of egg white was decreased during freezing storage.
By the salting out curve with (NH₄)₂SO₄, changes in globulin fraction of egg white was recognized from 30 days after freezing at -20°C. The foaming power of globulin fraction precipitated by (NH₄)₂SO₄ 0.45 saturated from frozen egg white was significantly lower than that of unfrozen egg white.
Tiselius's electrophoresis patterns in globulin+lysozyme, ovomucoid+flavoprotein and ovomucin fractions differed between unfrozen and frozen egg white stored for 30 days at -20°C.
From these results, it was seemed that decrease of foam property in egg white during freezing storage at -20°C was caused by changes in globulin and ovomucin

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From defatted soybean meal, crude protein fractions were prepared by means of a conventional method to fractionate 7S and 11S proteins (7 SPRF, 11 SPRF), basing on the difference of precipitation behaviors with calcium salt between both. The functional properties of those protein fractions were then investigated. The results showed; 1) The optimum temperature to form heat-induced gel was around 70°C with fish jelly (surimi), around 80°C with 7 SPRF and more than 90°C with 11 SPRF. Comparing with 7 SPRF, 11 SPRF formed hard and tough gel, specially having higher tensile strain. 2) Functional properties of surimi were quite different between commercial products prepared during winter and summer. Addition of 11 SPRF to surimi prepared during summer could improve its properties. 3) Comparing with 7 SPRF, 11 SPRF showed higher water capacity, keeping gel-forming properties. 4) Comparing with 11 SPRF, 7 SPRF showed slightly higher emulsifying capacity.

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FUKUSHIMA et. al. reported about the mechanism on the rapid decrease of the redispersibility of soy milk after drying in the manufacturing process. There is another trouble which occures during the storage of dried soy milk or soybean protein powder. The proteins contained in it are sometimes insolubilized during the storage of three months or so at room temperature or during oversea transportation. The cause was traced and it was concluded that the insolubilization was probably due to interactions of protein molecules by their SH groups or hydrophobic groups, when products were under powdered state. The reactions were accelerated when products had comparatively high moisture contents.

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