Analysis of Wine Samples for Free and Bound Smoke Taint Chemicals in Pinot Gris Samples by seq-SBSE-GC-TOFMS
GC-MS analyses of wine samples were conducted by a modified sequential-SBSE-GC-TOFMS method to compare concentrations of free and glycosidically bound smoke taint chemicals. Free volatile phenolics were determined by seq-SBSE-GC-TOFMS as described below. Then samples were retested after adjustment to pH 1.5, sonicated and heated to 100 °C to release the gylcosidically bound smoke taint (cresols, methyl guaiacols, guaiacol and syringol). Results are reported as free phenolic smoke taint volatiles and (gylcosidically) bound smoke taint phenolics.
The results provide an indication of the extent of smoke taint odor/flavor actively present in the wine and the potential for the release of additional smoke taint chemicals over shelf life. While fermentation tends to free gylcosidically bound chemicals, not all of these malodor chemicals may be released. Over time the smoke taint chemicals that remain bound to sugars in wine may be released, increasing the smokey malodor of the wine during shelf life storage.