LC-MS/MS METHOD TO EVALUATE THE PRESENCE OF EXOGENOUS GLYCEROL IN WINES

摘要

Glycerol is a natural constituent of wine being produced by yeast during fermentation and its concentration ranges between 5 and 11 g/L depending on yeast strain. It plays an important role on the sweet taste of wine [1]. The addition of synthetic glycerol to wines in order to increase this parameter is not allowed by the European oenological legislation [2]. Actually, the strategy to investigate the presence of exogenous glycerol in wine is based on the detection of impurities produced by the industrial processes on its production [3], which are absent in wines. Synthetic glycerol contains the follows impurities: 3methoxypropane-1,2-diol (3-MPD) and cyclic diglycerols (CycDs) formed during the purification of the rough industrial product conducted through a distillation process. Currently, the determination of these impurities are carried out by an GC/MS method after an extraction step in ethyl ether. As an alternative to this "old" method has been proposed an innovative approach based on liquid chromatography coupled to the mass spectrometry (LC-MS/MS).