This distinction is fundamental to understanding the stylistic diversity of white wines from the Jura. A topped-up wine (ouillé) is regularly replenished in the barrel to avoid any contact with air: it thus develops fruity and fresh aromas, similar to a Burgundian Chardonnay. Conversely, a wine aged under a veil (sous voile), or non-topped-up, deliberately leaves a space between the wine and the barrel bung. This void encourages the formation of a veil of Saccharomyces cerevisiae yeasts, which gives the wine its characteristic oxidative aromas: fresh walnut, almond, spices. It is this ancestral technique, unique to the Jura, that is at the origin of Vin Jaune and that makes this vineyard world-renowned for its originality.