Stainless Steel & Barrel Fermentation
Do you ever wonder why some wines, white or red, are brighter and fruitier than others? Or why some wines make your mouth water (acidity) vs pucker (tannin)? While the grape variety is the main contributor, the other is what vessel the wine is fermented in. The two main fermentation vessels are stainless steel tanks and oak barrels.
Stainless steel tanks contribute more freshness and accentuate more primary fruit found in the wines. You find aromatic white wines such as Riesling, Sauvignon Blanc, Pinot Gris, Melon and Albarino fermented in stainless steel to preserve their delicate fruit and vibrant acidity. Lighter, cool climate red wines such as Gamay, Pinot Noir, Barbera, Dolcetto are most suited for stainless steel for these same reasons.
Barrel fermentation adds a lot of nuance to a wine including texture, a richer mouthfeel, unique aromatics and flavors such as vanilla, cedar, spice, and subtle smokiness. You find richer white and red wines benefitting from the added nuance of barrel fermentation. For white wines, Chardonnay, Chenin Blanc, Viognier, Marsanne, Rousanne, and Gewurztraminer are commonly barrel fermented. Reds are almost always fermented in stainless steel and often aged in oak barrels for a period of time depending on their style and level of complexity.
Here are some key details highlighting and differentiating the different types of fermentation vessels:
Stainless Steel
Accentuates the freshness of the fruit in the wine
Stainless steel tanks were first advocated by Emile Peynaud during the early 1960s
Very efficient at controlling the fermentation temperature.
Make it easier to prevent oxidation
Is completely neutral in the winemaking process
Produce wines with greater fruit intensity; brighter style
Chateau Haut Brion was one of the first wineries in the world to install stainless steel tanks
Red wines are fermented between 75- 85 degrees
White wines are fermented between 50- 68 degrees
Oak Barrel
Have been used as a fermentation vessel for hundreds of years
Allows for greater use of lees contact and batonnage and malolactic fermentation
Can add additional level of complexity, flavor and aroma
Adds color too the wine and thus tannin
Fresh fruit aromas take on a more dried fruit quality as the yeasts extract the toasted, vanilla-like flavors from the wood
A secondary fermentation called Malolactic Fermentation (ML) usually will occur. The bacteria convert malic acid (tart) into lactic acid (as in dairy), making the wine creamier and rounder.
Oxygen and Texture play a greater role and have more influence