A Study on Pretreatment Method for Measuring Capsaicinoids of Chili Peppers using a Taste Sensor

Capsaicin, the pungent compound in chili peppers, is a non-charged substance, making it challenging to detect using taste sensors. In this study, capsaicinoids in chili peppers were extracted from cooking oil using liquid-liquid extraction and subsequently derivatized via a diazo coupling reaction. The negatively charged capsaicinoid derivatives were measured using a bitterness sensor (C00), which was developed to enhance hydrophobic interaction with acidic bitter substances. The results indicated that the sensor response was significantly higher for the chili pepper solution than for the blank and bell pepper solutions, and it increased in proportion to the capsaicin concentration. Furthermore, among chili peppers with different Scoville Heat Units (SHU), the sensor response correlated with SHU was also observed. Thus, this study demonstrated that the pretreatment method facilitates the rapid and simple measurement of capsaicinoids as pungency substances in chili peppers using a taste sensor.