In the vinification of red grapes, the choice of the most appropriate technique to enhance and optimize extraction is essential. The objective is to selectively extract the most noble compounds present in the skins, reducing the presence of bitter and vegetal flavour molecules.
The maceration techniques have evolved over time allowing to optimize the extraction process in the tank and overcome the limitations of those traditional techniques that did not allow to obtain totally satisfactory results.
An example are the fermentation technologies in open tank with punch-downs obtained through injection of air from beneath the cap, a technique which has been known for a long time but that has been little used in the past and is currently revolutionizing the processes of vinification of red grapes. It is a new technology that through modulated modifiable injections of air or inert gas, produces disintegrating waves that completely submerge the cap, flooding it with liquid, without mechanical actions.
Another type of selective maceration is fermentation in a closed tank with CO2 saturation, which uses the gas produced by the fermentation. A particular case is the ADCF system (for the Dynamic Analysis of Fermentation Kinetics) that monitors the fermentation process in real time by identifying the main phases of the process, such as the peak of maximum speed at which sugar is consumed, on an industrial scale in tanks of any shape and size. That is to say, it allows to apply, in the cellar and in practice, concepts widely studied at a theoretical level. Experimental tests have permitted to evaluate how the control of the interactions between maceration techniques and the overpressure produced by CO2 can actively influence and favour the extraction of polyphenolic compounds.
The papers by Leo Forte, Parsec, and Alessandra Biondi Bartolini, I + D Consultant, on the occasion of Enoforum 2018, offer an overview of the functioning and the characteristics of these maceration techniques, they display the results obtained in various experimental tests and illustrate the future possibilities of application of these vinification systems.
The reports reproduced in these films were presented at the 11th edition of Enoforum (Zaragoza, 31 May-1 June 2018) within the module organized in cooperation with Parsec