Innovative “Soft” Maceration Techniques in Red Grape Fermentation

Abstract

Two innovative soft maceration techniques of vinification based on red grape Cabernet Sauvignon were compared in 2020 and 2021 vintages with the most used system of maceration (pump-over and delestage) in today’s wine sector in order to verify the efficiency in polyphenol extraction and fermentation rate. Fermentation kinetics and final wine characteristics were evaluated as the main parameters for comparing the systems. The AIR MIX (AIRMIXING M.I.™) technique is based on the use of a fixed sequential small injections of compressed air (3 jets) from the bottom of the tank, aimed at creating waves (resonance waves) able to prevent the cap formation. The ADCF (NECTAR-ADCF™) technique uses the overpressure produced by carbon dioxide in the wine tank during alcoholic fermentation to keep the cap submerged and to favor its disruption by the CO2 outside release through a valve. As a reference, the control vinification consisted of the use of “delestage” and pump-over to facilitate the extraction and good management of the cap. ADCF, at the end, extracted a greater quantity of polyphenols and anthocyanins. AIR MIX speeded up the fermentation, which ended 4–7 days before the control and, initially, provoked a greater extraction of phenols and anthocyanins as ADCF. By the end, the concentration of polyphenols and anthocyanins was the highest in ADCF, followed by control and AIR MIX approximately at the same amount. The control wine had a slightly higher volatile acidity. AIR MIX consumed more than 60% less energy because the nonuse of pump-over and delestage, and also, no personnel was requested.