Effect of serving temperatures on retronasal detection thresholds of capsaicin and dihydrocapsaicin among Korean consumers

The purpose of this study was to determine the retronasal threshold values of capsaicin and dihydrocapsaicin according to the change in serving temperatures. Threshold tests were performed using five series of three alternative forced choice method in aqueous-based matrices at varying temperature levels. The retronasal threshold values of capsaicin at 4°C, 25°C, and 60°C were 1.83, 1.57, and 1.57 mg/kg, respectively; no significant differences were observed. Similarly, the retronasal threshold of dihydrocapsaicin at 4°C, 25°C, and 60°C reached 2.14, 1.71, and 1.78 mg/kg, respectively; no differences based on serving temperature were observed (p >.05). These values were slightly higher than best estimate thresholds reported in different countries. Practical Applications: Capsaicin and dihydrocapsaicin are two of the major compounds responsible for how we perceive spiciness in food. This study found no differences in best estimate thresholds (BETs) according to the temperature at which the food was served, suggesting that the serving temperature does not impact the recognition threshold of capsaicin and dihydrocapsaicin. This means that the serving temperature does not alter the human perceived spiciness in foods having capsaicin and dihydrocapsaicin above BET levels.