Barrel fermented is a word that you often see on bottles of white wine.
Do you know exactly what it means? And why it is often highlighted on a label?
In general when a wine label says ‘Barrel Fermented’ it is highlighting an oak influence on the wine.
While theoretically any size of barrel can be used, the term usually is an indication that the wine was fermented in small oak barrels called barrique (60 US gallons / 225 liters).
Wines that are barrel fermented taste different from wines that have been fermented in stainless steel (the most common fermentation vessel for both white and red wines). Barrel fermented wines are more about highlighting texture, structure and mouthfeel than up-front, well-preserved primary fruit aromas and flavors.
Not just about oak aromas and flavors: As well as imparting some oak flavor (toasty notes, vanilla, spice etc.), barrel fermented wines have a rounder, broader mouth feel and firmer structure. This is because oak is not inert and allows some air (oxygen) ingress.
Barrel fermented wines also have more lees contact. Lees are dead yeast cells. As these yeast cells break down they release all sorts of compounds such as proteins and amino acids into the wine, contributing a textural creaminess and yeasty character.
In summary barrel fermented white wines are more about the secondary characteristics generated during fermentation than upfront primary fruit.
Barrel Fermentation vs. Barrel Aging: When a wine is fermented in barrel vs. being put in barrel after fermentation to age, the oak influence (i.e. oak aromas and flavors) is less upfront. The oak tends to be better integrated in the wine and less of an overlay. It is more subtle and less overpowering of the fruit, which should still be evident and well defined.
While any white wine can be barrel fermented it is most commonly associated with the Chardonnay grape and other less strongly aromatic grape varieties.