Sonication of White Grapes vs Prefermentative Skin Maceration: Effect on Aroma Compounds and Sensory Properties in Airén and Macabeo White Wines

Abstract The use of high-power ultrasound (US) has been extensively studied in red winemaking, whereas its application in white winemaking, particularly from low‑aromatic varieties, remains insufficiently explored. As US has been proposed as an alternative to prefermentative cold maceration (PM), this study evaluated the physicochemical parameters, polysaccharide profile, volatile compounds, and sensory attributes of two low-aromatic varieties (Macabeo and Airén), vinified by direct pressing (C), or after PM (4 h) or US treatment prior pressing. Distinct responses to the applied treatments were observed in the two varietal contexts. Macabeo wines produced with US-treated grapes showed similar outcomes to PM vinification, although the processing time is reduced by 4 h. Both treatments enhanced terpenes and norisoprenoids concentration in musts and wines, with US treatment exerting the strongest effect and also exhibiting higher ester, acetate, and lactone concentration, consistent with the fruity-floral sensory notes detected in the wines. In contrast, in Airén wines, a slight browning and minor aromatic improvements were observed, although US treatment increased mouthfeel structure and led to a greater astringency, body, and aftertaste intensity. Overall, these results confirm high‑power ultrasound as an effective extraction technique in white winemaking, with relevance depending on varietal context and winemaking objectives.