A salt substitute composition is provided. The salt substitute composition has an amount of potassium chloride and an amount of N-[N-(3,3-dimethylbutyl)-L-.alpha.-aspartyl]-L-phenylalanine 1-methyl ester or neotame. The N-[N-(3,3-dimethylbutyl)-L-.alpha.-aspartyl]-L-phen- ylalanine 1-methyl ester is present in an amount of about 0.001 wt % to about 0.02 wt % of the total weight of the composition. The amount of N-[N-(3,3-dimethylbutyl)-L-.alpha.-aspartyl]-L-phenylalanine 1-methyl ester is optimized for reducing the undesired aftertaste of the potassium chloride.