Determination of semi-volatile additives in wines using SPME and GC-MS

Parameters of headspace solid-phase microextraction, such as fiber coating (85 mu m CAR/PDMS), extraction time (2 min for white and 3 min for red wines), temperature (85 degrees C), pre-incubation time (15 min) were optimized for identification and quantification of semi-volatile additives (propylene glycol, sorbic and benzoic acids) in wines. To overcome problems in their determination, an evaporation of the wine matrix was performed. Using the optimized method, screening of 25 wine samples was performed, and the presence of propylene glycol, sorbic and benzoic acids was found in 22, 20 and 6 samples, respectively. Analysis of different wines using a standard addition approach showed good linearity in concentration ranges 0-250, 0-125, and 0-250 mg/L for propylene glycol, sorbic and benzoic acids, respectively. The proposed method can be recommended for quality control of wine and disclosing adulterated samples. (C) 2016 Elsevier Ltd. All rights reserved.