Bâtonnage Winemaking Techniques

You want to add extra body and mouthfeel to your wines, or perhaps enhance those buttery or yeasty aromas and flavors in your barrel-fermented Chardonnay? Or maybe even round out those sharp tannins in young reds? Then you may want to consider lees stirring, or what the French call bâtonnage, the technique of stirring dead wine yeast cells with a “stick.” Lees stirring is commonly practiced in making rich, full-bodied, oak barrel-fermented whites, particularly Chard-onnay, as well as in sur-lie-style Melon de Bourgogne-based wines of Muscadet de Sèvre et Maine in the Loire Valley; in reds, it can be used to soften tannins and stabilize color. Lees stirring also improves colloidal and cold stability, thereby reducing the risk of hazing and tartaric salt crystallization. It can also be used to enhance lactic acid bacteria growth where malolactic fermentation (MLF) is desired. What’s not to like about lees stirring? But the technique can prove disappointing and even disastrous if not performed properly and in a timely fashion. Here we will look at the underlying physical chemistry and biochemistry of Saccharomyces cerevisiae