Modification of the polyphenolic and aromatic fractions of red wines aged on lees assisted with ultrasound

摘要

The ageing on lees is a technique particularly interesting in the production of red wines due to the possibility of enhancing some of their sensory characteristics. Different authors have researched the ultrasound assistance to accelerate this ageing process in wines. The present work evaluated the modification that both fractions, polyphenolic and aromatic, of red wines suffer during the ageing on lees process assisted with ultrasounds and with the addition of oak chips. The results obtained during the experimental design indicate that the ultrasound treatment decreased the concentration of proanthocyanidins (between 20.3% and 32.8% with and without oak chips, respectively) and the total pigment content (with the highest reduction in the control sonicated wine 55.9% without chips and lees and from 47.8% to 48.9% when having oak chips/lees and lees, respectively). In addition, it has been observed that the ultrasound treatment did not affect the amount of fermentative volatile compounds present in the wine but, it increased the concentration of phenolic aldehydes coming from oak wood chips (10.8% in control wine and from 35.92% with oak chips/lees to 55.8% with lees).