The taste of several bitter amino acids is reduced, sourness produced, and preference increased by γ-glutamylization. An enzymatic method for synthesizing γ-Glu-Val involving bacterial γ-glutamyltranspeptidase (GGT) was developed. The optimum reaction conditions for the synthesis of γ-Glu-Val were 20 mM Gln, 300 mM Val, and 0.04 U/ml GGT, pH 10. After 3-hr incubation at 37° C, 17.6 mM γ-Glu-Val was obtained, with the yield being 88%. γ-Glu ...