中性およびアルカリ性小麦粉生地の種々酵素活性について

抄録

Using an extract or suspension of wheat flour (Dark Hard Winter), various enzymes were assayed under neutral or alkaline conditions. Besides amylases, proteolytic enzymes, peroxidase and lipoxidase, the following enzymes were detected with activities shown below (One unit of activity was the enzyme amount that degraded 1 μmole of substrate or produced 1 μmole of reaction product in every min at 30_??_40°C. The activity unit was expressed per 1g of flour.): α-D-galactosidase, 1.0; β-D-galactosidase, 0.02; β-D-glucosidase, 0.8; phosphatase, 2.5; lipoamide dehydrogenase, 0.5 at pH 5.8. Esterase activity was about 6.0 at both pH values of 5.8 and 9.5. Glutamic acid dehydrogenase and S-alkylcysteine lyase were 0.4 and 1.1, respectively, at pH 9.5.
The characteristic properties of dough made by use of a dilute saline and alkaline solutions, respectively, were discussed in connection with the flour enzymes which were active at neutral and alkaline sides. Also, wheat flour was suggested to be a good source of some of the enzymes examined, because the soluble protein of flour in 0.1% NaCl solution is around only 1.5% of flour.