AIR-ENTRAINING AGENT FOR CEMENT POSITION AND CURING OF CEMENT COMPOSITION CONTAINING THE AIR-ENTRAINING AGENT

摘要

PROBLEM TO BE SOLVED: To obtain a cement composition exhibiting an excellent air-entraining function even when compound with fly ash, by adding the enzymatic hydrolysate of soybean protein as an active ingredient. ;SOLUTION: The cement composition is used in a state of a cement paste, mortar, concrete or the like. The cement includes the ordinary cement and a cement-based solidifying agent such as a soil cement. The protease used is suitably a protease exhibiting the activity at pH 3.0 or lower, and includes pepsin. The protease is preferably a protease exhibiting the activity at a reaction temperature of 55-85°C. The extent of the hydrolysis of the soybean protein is preferably ≥20 wt.% as a 0.22 mole trichloroacetic acid soluble rate. The enzymatic hydrolysate of the soybean protein is prepared by adding 40°C hot water to low denaturated defatted soybean flakes, adjusting the mixture to pH 7.0, extracting for 1 hr, removing an insoluble fraction, adjusting the obtained defatted soybean cured with hydrochloric acid to pH 2.0, adding pepsin, enzymatically hydrolyzing the protein at 60°C for 1 hr, adjusting the hydrolysate to pH 7.0, and then spray-drying the hydrolysate.;COPYRIGHT: (C)2000,JPO