Method for crystallizing alpha -L-aspartyl-L-phenylalanine methyl ester

摘要

A method for crystallizing alpha -L-aspartyl-L-phenylalanine methyl ester from a hot aqueous solution containing alpha -L-aspartyl-L-phenylalanine methyl ester by cooling is disclosed, which comprises (i) continuously supplying a hot aqueous solution of alpha -L-aspartyl-L-phenylalanine methyl ester having a concentration such that the content of L-aspartyl-L-aspartyl-L-phenylalanine methyl esters is less than 0.6% by weight based on the weight of alpha -L-aspartyl-L-phenylalanine methyl ester in said solution, or if the content of L-aspartyl-L-aspartyl-L-phenylalanine methyl esters is 0.6% by weight or more based on the weight of alpha -L-aspartyl-L-phenylalanine methyl ester in said solution, to a crystallization vessel the temperature of which is lowered to that corresponding to the solubility of alpha -L-aspartyl-L-phenylalanine methyl ester or less, and (ii) continuously discharging the formed slurry from the crystallization vessel.