Therefore, the FFA were expected to influence goaty flavor when they were present at supra-threshold concentrations in milk, and they might also have expressed goaty flavor by synergistic effects when they were present at low concentrations in milk. It should be noted that thresholds depend greatly on the expertise of panelists and character of media (such as pH), thus the thresholds of FFA differ among studies (Brennand et al., 1989).