Abstract: In the present study, an ultra-high performance liquid chromatography (UPLC) method and a high performance liquid chromatography (HPLC) method were developed for the determination of tetramethylpyrazine in Zhenjiang balsamic vinegar and related products. Tetramethylpyrazine was extracted from samples with acidic ethanol aqueous solution. The mobile phase was a mixture of 25% methanol and 75% acidic aqueous solution (containing 1% acetic acid and 0.05% trifluoroacetic acid, pH 2.4). A C18 column with small packing particle size (2.1 mm × 100 mm, 1.5 μm) was used in UPLC while an SB-C18 column (4.6 mm × 250 mm, 5 μm) was used in HPLC. The flow rates of the columns were 0.3 and 0.8 mL/min, respectively, and the detection wavelength was set at 297 nm. The calibration curves obtained were linear over the range of 0.50–50.00 μg/mL. The mean absolute recoveries were at least 87.9% with relative standard deviations less than 3%. The retention time of tetramethylpyrazine was 1.6 min in the UPLC method compared to 9.7 min in HPLC. Moreover, the limits of detection (LODs) of the two methods were 0.000 3 and 0.008 g/kg, respectively, and the limits of quantitation (LOQs) were 0.001 and 0.025 g/kg, respectively.

Key words: tetramethylpyrazine, vinegar, Zhenjiang balsamic vinegar, ultra-high performance liquid chromatography, high performance liquid chromatography