Discrimination thresholds for glutamic acid and chicken oil in chicken broth assessed by an untrained panel at a research institute

Glutamic acid (Glu) and fat are recognized as primary flavor components in meat. This study aimed to determine the discrimination threshold of an untrained panel for Glu and fat in meat. Thirty-two untrained panelists were recruited among research institute employees. First, triangle tests were performed using chicken broth supplemented with Glu at concentrations of 10, 50, 110, and 200 μg/ml and broth without Glu supplementation (control). The Glu supplementation test did not distinguish between Glu-supplemented broth and the control. Thus, the discrimination threshold for Glu in chicken broth was determined to be >200 μg/ml. Second, triangle tests were performed using chicken oil-emulsified broth at concentrations of 43, 129, 387, and 1160 μg/ml and broth without chicken oil supplementation. The probability of choosing the correct sample in the triangle test for each chicken oil concentration was calculated. The probit regression analysis estimated the discrimination threshold for chicken oil in chicken broth to be 341 μg/ml among untrained panelists. Although the number of untrained panelists recruited in this study was limited, our results provided useful findings for evaluating and improving meat quality utilizing Glu and fat content.