Influence of Pulsed Electric Fields on aroma of Garnacha wine

MARCOS MAZA; GUILLERMO SALDAÑA; JAVIER RASO; IGNACIO ALVAREZ

Conferencia; EFFoST International Conference 2017 - EFFoST; 2017

Phenolic compounds and aroma play a very important role in the quality of red wine. Although grape musts do not show intense or explicit flavors, after must fermentation the obtained wine has usually pleasant aromas that may be related to the varietal origin. These compounds are affected by oenological practices. The effect of pulsed electric field on the improvement of the extraction of polyphenols during maceration-fermentation step of red winemaking has been extensively investigated. However the effect of these treatments on the aromatic profile of wines obtained from grapes treated by PEF is unknown. The objective of this investigation was to evaluate the effect of PEF on the aromatic profile of wines obtained from grapes treated by PEF with different maceration times.PEF treatments were conducted at a flow of 2500kg/h with an EPULSUS® modulator (EnergyPulseSystems) at 4 KV/cm using a colineal treatment chamber with two treatment zones of 2.5 cm of gap and 3.5 cm of internal diameter. Tanks with 3000 kg of Garnacha grapes were used for obtaining wines with 3 and 6 days of maceration for untreated and PEF treated grapes.Results obtained show that wine obtained with grapes treated by PEF and 3 days of maceration had similar total polyphenols (TPI), color intensity (CI), total anthocyanins (ANT) and condensed tannins (TA) than the control wine obtained after 6 days of maceration. On the other hand, the content of important volatile compounds (higher alcohols and some of their acetates, methionol, butyrate isobutyric acid Ethyl acetate and hexanoic and octanoic acids) were higher for the wine obtained with 3 days of maceration with PEF treated grapes. According to these results, the PEF treatment permitted reducing maceration time for 3 days and obtaining a wine with more aromatic compounds without affecting the total polyphenolic content of the wine.