beta -Lactoglobulin was enzymatically acylated with N-lauroyl-L-glutaminyl-glycine and N-lauroyl-L-glutamyl-L-lysine using transglutaminase from Streptomyces mobaraense. The modification of the protein with N-fatty-acyl-dipeptide was confirmed by SDS-PAGE, gel chromatography, HPLC, amino acid analysis, and TOF-MS. The degrees of the protein modification with N-lauroyl-L-glutaminyl-glycine and N-lauroyl-L-glutamyl-L-lysine were estimated to be 2-4 and 1.5 residues per molecule, respectively.