Determination of Volatile Phenols in Wine by Gas Chromatography Tandem Mass Spectrometry with Distillation and Liquid-Liquid Extraction

A method for determination of volatile phenols in wine by gas chromatography tandem mass spectrometry (GC-MS/MS) with distillation and liquid-liquid extraction was proposed. 100 mL of wine sample (liquid temperature of 20 ℃) was taken and put into a 500 mL-distillation bottle, connecting the condenser tube for distillation. 100 mL of distillate was collected, 20 mL of which was taken and put into a 50 mL-centrifuge tube. 20 μL of internal standard solution (ethanol solution containing 25.0 mg·L^-1 3,4-dimethylphenol) was added, and the mixture was oscillated by vortex for 5 min and mixed well. Sodium chloride was added to reach saturation (sodium chloride mass concentration of 360 g·L^-1). The solution was extracted with 10 mL of dichloromethane (5 mL/time×2 times, oscillation for 5 min, ultrasound for 10 min and centrifugation for 5 min for each extraction), and the combined organic phase was dehydrated with 3.0 g of anhydrous sodium sulfate and blown to 1 mL by nitrogen at 35 ℃. 14 volatile phenols in the obtained solution were determined by GC-MS/MS. As shown by the results, linear relationships between the mass concentration ratios of 14 volatile phenols to internal standard and the corresponding peak area ratios were found in definite ranges, with detection limits (3S/N) in the range of 0.5-9.2 μg·L^-1. Test for recovery was carried out according to the standard addition method, giving results in the range of 87.3%-107%, with RSDs (n=6) of the determined values in the range of 0.70%-5.6%.