Puttin' On the Heat: Fermentation Time in the Cellar

We may be done harvesting grapes, but there is still a lot of work to do. As I write this, some fermentations are still active. Our Santa Cruz Mountains Chardonnay, which is entirely barrel-fermented using native yeast, can take up to five months to complete primary and secondary fermentation—the conversion of malic acid (tart) in the grapes to lactic acid (soft, buttery quality). 

Our other wines are fermented in stainless steel tanks. We make sure that the wines are fully fermented (all of the sugars have been converted to alcohol). At that point, the skins are pressed and the wine is transferred to settling tanks to settle out the solids before putting the wine in barrels. Primary fermentation takes two weeks. Then a new process begins: secondary fermentation, which is a bacterial activity that generally occurs in-barrel. All red wines go through malolactic fermentation (ML) to ensure stability. ML can take a long time so we monitor it until completion, around the start of the new year.   

Cheers,
George Troquato, Winemaker