The disclosure relates to a method for hydrolyzing lignocellulose to form a hydrolysis product comprising adding water and an acid catalyst to a reaction mixture comprising (a) an ionic liquid in which cellulose is at least partially soluble and (b) lignocellulose, wherein the timing and amount of water added is controlled such that the polysaccharide of the lignocellulose is not precipitated from the reaction mixture and hydrolysis is not substantially inhibited, and wherein acid catalyst is added in an amount sufficient to initiate hydrolysis, wherein the reaction mixture is heated to a temperature of about 70 to 140°C, wherein water is added until the total amount of water is at least 20 weight% of the reaction mixture, and wherein hydrolysis is continued until monosaccharide yield in the hydrolysis product is 50% or higher.
