Determination of capsaicin and dihydrocapsaicin in air in a pickle and pepper processing plant

A sampling and analytical method has been developed for measurement of capsaicin and dihydrocapsaicin in air. This method is applicable to measurement of the capsaicinoids in air in pepper processing plants and involves air sampling with a 13-mm glass fiber filter, recovery of the sample with 2 mL of acetonitrile, filtration of the solution, and analysis by high performance liquid chromatography with fluorescence detection. Excitation and emission wavelengths of the detector were 281 and 312 nm, respectively. Average recoveries were 98 to 104% after fortification of glass fiber filters with 0.13- to 2.9-microg quantities of capsaicin. Average recoveries of dihydrocapsaicin were 93 to 99% after fortification of glass fiber filters with 0.11- to 3.0-microg quantities. Detection limits of capsaicin and dihydrocapsaicin were 0.015 and 0.02 microg per sample, respectively. This method was used successfully for determining air concentrations of capsaicin and dihydrocapsaicin in a health hazard evaluation at a large pickle and pepper processing plant. An interesting phenomenon was the fact that the ratio of capsaicin to dihydrocapsaicin in each of the largest air samples was in the range of 0.3:1 to 0.5:1. Generally, capsaicin is the capsaicinoid that occurs in Capsicum fruit in the greatest relative abundance.