Colorimetric Determination of Capsaicin in Capsicum Fruits

Abstract A simple and accurate colorimetric method has been developed for quantitative determination of capsaicin in capsicum fruits. The method does not involve prior isolation of capsaicin from green capsicum fruits, and interference due to pigments is accounted for by determining a blank. Interfering substances are removed from red capsicum fruits by column chromatography using basic alumina as adsorbent. Capsaicin from the ethyl acetate extract of dried fruits is determined by developing a yellow complex with sodium nitrite–sodium molybdate reagent, which is read at 430 nm. Lambert-Beer’s law is obeyed in the concentration range 1.5–33.5 μg capsaicin/mL. The method is reproducible and is applicable to the rapid determination of capsaicin content.