Mobile phases in reverse-phase HPLC for the determination of bitter peptides in cheese

A cheese extract and a standard solution with a mixture of peptides and amino acids were used to evaluate the separations of reverse-phase HPLC with alternative mobile phases to be used in conjunction with sensory evaluation. Acceptable resolution of components was observed when acetonitrile was replaced with absolute ethanol and trifluoroacetic acid was replaced with food-grade hydrochloric acid. The average hydrophobicity and molecular weight of the peptides and amino acids were used to construct a linear regression equation with corrected retention times. Suspected bitter compounds were not confined to any one section of the chromatogram based on the established regression model.