Influence of electric field intensity on to improvement of extraction of polyphenols during vinification of Garnacha grapes

MAZA, MARCOS ANDRÉS; JAVIER RASO, IGNACIO ALVAREZ

Viena

Taller; 4th PEF School; 2017

University of Natural Resources and Life Sciences, Vienna

After 4 days of maceration wines, no significant differences were found between the wines obtained from grapes treated at 6 and 8 kV/cm. However, the TPI, CI and ANT of these wines were 28, 25 and 30% higher as compared with the control with the same maceration time and these indexes were even higher than those obtained for the wine with 12 days of maceration. After 6 days of maceration, the wines treated at 1 and 4 kV/cm showed higher TPI, CI and ANT than the CS12. No significant differences were observed between the wine obtained from grapes treated at 4 kV/cm with the two different modulators. The TPI and ANT for the wine obtained from grapes treated at 1 kV/cm were significantly lower than for the wine obtained from grapes treated at 4 kV/cm. According to the results obtained in this research, a treatment at 6 kV/cm with a total specific energy of only 6 kJ/kg permitted decreasing the maceration time for 9 days. Treatments at lower electric field strengths required extending the maceration time for 2 days more in order to obtain wines with similar indexes that those obtained at 6 kV/cm