LAUSR

BACKGROUND High-power ultrasound technique is a novel and non-thermal technique normally used in red vinification to increase the extraction of phenolic compounds. However, few studies have been carried out on its effect on the extraction of aroma compounds and their precursors in white grapes. This study evaluates the effect of high-power ultrasounds at winery-scale in the maceration of Viognier grapes on the content of varietal volatile compounds (free and glycosidically bound) in musts and wines, in comparison with wines from direct pressing and from short skin maceration. RESULTS The prefermentative ultrasound treatment of the grapes produced an increase in most of the varietal compounds of musts and wines, both in the free fraction and in the bound one, especially in the C6 alcohols, terpenes and norisoprenoids, some of them of sensory relevance, while the effect on esters and lactones was less evident. Ultrasound maceration allowed to obtain wines of higher aromatic intensity , with a more pronounced varietal character,. CONCLUSION The prefermentative ultrasound treatment of Viognier grapes increases the aromatic potential of the wines, as it favors the extraction of the free and bound varietal volatile compounds. In addition, it allows the maceration time of the grapes to be reduced compared to conventional pre-fermentation techniques, thus avoiding oxidative processes that could negatively affect the aroma of the wines. This article is protected by copyright. All rights reserved.