Combining high-power ultrasound and enological enzymes during winemaking to improve the chromatic characteristics of red wine

Several techniques have been used by the winemaking industry to facilitate the extraction of grape phenolic compounds during the maceration process. Interest in innovative techniques such as high-power ultrasound (US) has increased in recent years, replacing more traditional techniques such as the addition of pectolytic enzymes (E). This study evaluates the combined effect of ultrasound and enological enzymes, used at semi-industrial scale at the time of crushing, on the chromatic characteristics of red wine. Variables such as the timing of enzyme addition and the ripening state of the grapes were considered. The results showed that ultrasound had a greater effect than enological enzymes when used alone, especially when the ripest grapes were used. The results also indicate that, when added after sonication, the enzymes favored the US effect, enabling the contact time necessary to achieve a wine with chromatic characteristics similar to those resulting from a traditional maceration process to be reduced by 4 days. Carried out on a semi-industrial scale, the study demonstrates that the adequate combination of these two techniques can optimize the maceration process both in terms of time and the wine organoleptic characteristics, making the technique of special interest for industrial application.