GAS-CHROMATOGRAPHIC AND MASS-SPECTROMETRIC STUDY OF FERMENTATION PRODUCTS FROM VARIETAL GRAPE MUST (RED BOBAL), WITH AND WITHOUT SELECTED KILLER YEAST

Selection of a particular yeast strain can provide better control over the fermentation process; the use of a select yeast strain can improv e resulting wine quality. For these reasons, yeast selection is a rout ine practice in winemaking. The active dry yeast L-2226 was employed a s the starter culture in this investigation; it was chosen for its spe cial fermentation characteristics and suitability to the winemaking pr actices of the region (wines with high concentrations of sugars). The role of L-2226 cultures in aroma production was studied over Bobal var iety must, using capillary columns and gas chromatography-mass spectro metry (GC/MS). For comparison purposes, two classes of fermentation we re carried out: on a single grape must of Red Bobal: (a) indigenous ye ast and (b) a selection of Killer yeast L-2226. The differences in the aroma components for both treatments are discussed.