PURPOSE: To obtain the subject composition consisting of a hydrophilic surfactant, a hydrophilic polymer compound and dextrin powder having specific physical properties, being high in safety, readily handleable and compact and excellent in stability, foaming properties and water-soluble property.

CONSTITUTION: This composition is composed of a hydrophilic surfactant (e.g. a nonionic polyoxyethylene 12-15C alkyl ether, preferably having ≥10HLB and <2% water content), a hydrophilic polymer compound (e.g. methyl cellulose) and dextrin powder having physical properties of ≤5% water content, 15-30cps viscosity (at 20°C in 30% aqueous solution), pH4 to 5.5, 10-20 specific volume, ≤0.1% ash content and ≤50° angle of repose.