PURPOSE:To improve both emulsion stability for a long period and death ratio of thermostable bacterial spores, by blending a coffee beverage containing milk components consisting of an aqueous extract solution of coffee, milk component and sweetener with a lysolecithin. CONSTITUTION:A coffee beverage prepared by blending an enzymically improved lecithin consisting essentially of a lysolecithin (1-monoacylglycerophospholipid) obtained by improving lecithin (1,2-diacylglycerophospholipid) derived from natural products by enzymic hydrolysis with a coffee beverage containing milk components. Since hydrating power is several times based on that of lecithin, the lysolecithin is hardly affected by temperature and pH, etc., and assumes excellent surface activating effects. Thereby emulsifying and dispersing powers are remarkable with great effects on suppression of suspended substances occurring with time. The lysolecithin is capable of acting on cell membranes on the surfaces of cells, yeasts and molds and inhibiting germination and propagation of microorganisms. As a result, putrefaction and deterioration of the coffee beverage are prevented without requiring special treatment in production and stable preservation can be carried out for a long period.