Just like bread, yeast in winemaking facilitates fermentation. The sugars in must (grape juice) magically transform into alcohol under the presence of these eukaryotic microbes. Yeast can occur naturally on grape skins and be used for primary fermentation, or winemakers can choose to add yeast to initiate the start of fermentation.

For Untamed: we add yeast to our juice to better control primary fermentation. Fermentation is a critical period during the winemaking process, and any off-balance in the byproducts produced during fermentation (heat and carbon dioxide) can create permanent damage to a potentially great wine. We select yeast strands that are compatible with each varietal and have a history of reliable ferments.

Mixing yeast to inoculate a tank of grape juice.

Lees and Sur Lie (Lie pronounced like Lee)

Once the little yeasts have converted the sugar to alcohol and the fermentation is over, they die. The cells break down in a process called autolysis and fall to the bottom of the vessel.

These dead yeast cells are super important for white wine aging and sparkling wine aging. In letting the wine sit on these lees (a process called sur lie), the wine absorbs beneficial textures and flavors. Ever heard of a wine described as: creamy, rich, great depth, full bodied, and complex? This wine has most likely been aged sur lie.

To gain all the benefits of sur lie, winemakers stir the lees during aging in a process called batonnage. Batonnage upsets the lees to homogenate the great flavors and textures throughout the entire barrel of wine. This process generally occurs when sur lie aging Chardonnay, batonnage gives this varietal it’s characteristically full bodied and buttery complexity.

Sparkling wines are also typically aged sur lie. French Champagne and South African MCC sparkling wines are in fact regulated and must spend at least 12 months aging sur lie.

Sur Lie aging in a sparkling wine bottle.


Looking to try a sur lie aged wine?

2021 Untamed Chardonnay: fermented in barrel and aged sur lie for 8 months, our Chardonnay is a classic example of sur lie aging in a still white wine. Creamy, full bodied, with all the benefit of the lees and not hidden by a ton of oak. Come in and try a sample or purchase a bottle online here:


2020 Blanc de Blancs: Just like Champagne, our sparkling wine has been aged sur lie for 18 months. Expressing flavors of toast and buttermilk pancakes – without all the carbs. This is an elegant sparkling wine and has great aging potential. This is ultimately one of our favorites and best sellers at Untamed: