Influence of `Novarom G' Pectinase β-glycosidase Enzyme on the Wine Aroma of four White Varieties

Abstract

Knowledge of the aroma precursors in enology has been fundamental in studying the aromatic potential of grape varieties. These precursors, represented fundamentally by the glycosidically-bound aroma compounds, are present in the grape at higher concentrations than the free or volatile forms. Acid hydrolysis of these precursors is not a viable way to produce significant chemical modifications in terpenes, but enzymatic hydrolysis is the best technique to increase the concentration of the free aroma fraction in wines. As a result, current studies are focused on the use of β-glycosidase enzymes to hydrolyze and release these aroma precursors as a way to improve the characteristics and sensory quality of wines. This work describes the influence that the application of `Novarom G' β-glycosidase enzyme has on the aromatic composition of monovarietal wines from four white varieties: Palomino fino, Sauvignon blanc, Traminer, and Viura. The grapes were cultivated in an experimental vineyard at the IFAPA Centro `Rancho de la Merced' (Jerez de la Frontera). Enzyme-treated wines showed significant differences in comparison to the controls in terms of analytical data: the terpenes and 2-phenylethanol concentrations increased in all varieties. The resulting wines had a more floral and fruity aroma and an improved sensory quality.