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Formation of 4-vinyl guaiacol in adversely stored orange juice as measured by an improved HPLC method

4-Vinyl guaiacol, a potent off-flavor compound in orange juice, was isolated by using a C-18 cartridge and analyzed by high performance liquid chromatography (HPLC) with fluorescence detection. The new HPLC method possessed a sensitivity of 10 ppb for 4-vinyl guaiacol and was at least 5 to 10 times more sensitive than previously reported gas-liquid chromatographic procedures. Storage of bottled orange juice for 18 wk yielded the following 4-vinyl guaiacol levels: 42 μg/L (20°C), 223 μ/L (30°C), and 778 μg/L (40°C). Concentration of 4-vinyl guaiacol increased with storage time at all storage temperatures; however, a noticeable decrease occurred after extended storage at 50°C.