Determination of Capsaicin and Dihydrocapsaicin in Capsicum (Capsicum annuum) Products by High Performance Liquid Chromatography-Fluorescence Detection (HPLC-FLD).

[Objectives] This study was conducted to determine capsaicin and dihydrocapsaicin in capsicum products. [Methods] The sample was ultrasonically extracted with anhydrous ethanol as the extraction solvent for capsaicin and dihydrocapsaicin, followed by centrifugation. The extract was subjected to HPLC separation with methanol-water (65:35) as the mobile phase, and a fluorescence detector (Ex = 229 nm, Em = 320 nm) was used to detect capsaicinoids in the sample. [Results] Capsaicin and dihydrocapsaicin had a good linear relationship in the range of 1-200 mg/L (R1² = 0.999 8, R2² = 0.999 6). The detection limits were both 0.007 mg/kg; the quantification limits were both 0.02 mg/kg; the precision was 0.235% and 0.754%, respectively; and the average recoveries were 95.94% and 95.39%, respectively. [Conclusions] The method is simple, rapid, with good sensitivity and precision, and is suitable for detecting capsaicin substances in capsicum products. [ABSTRACT FROM AUTHOR]