Determination of volatile acids in tobacco, tea, and coffee using derivatization-purge and trap gas chromatography-selected ion monitoring mass spectrometry

Short-chain organic acids from agricultural products are simultaneously extracted and derivatized using methanolic hydrochloric acid. Acetic, isobutyric, butyric, isovaleric, valeric, hexanoic, 3-methylvaleric, heptanoic, and nonanoic acids are quantitated using purge and trap gas chromatography with selected ion monitoring mode mass spectrometry. Flue-cured, burley, and oriental tobacco varieties are compared based on their volatile organic acid content. Commercial coffee, tea, and three cigarette brands are analyzed, and their differences are evaluated to demonstrate the utility of this technique for natural product analysis.