Wine Aging: Oak Barrels vs. Stainless Steel Tanks
The grapes are harvested, crushed and fermented. Next, in the vinification or winemaking process is aging. Lasting 5 months to several years, in stainless steel or wooden barrels, preferences range from heavily toasted wood for strong, prominent flavors to no wood aging. Is one better than the other? What’s the difference?
Aging in stainless steel is neutral, it adds nothing more to wine than a container to hold it as it evolves and matures before bottling. Winemakers who steel age believe it “allows the grape varietal to speak without any influence of wood”. They maintain the terroir (vineyard’s elevation, type of soil, position of a hill or slope, weather nuances, orientation to the sun) is more clearly expressed in steel aging, resulting in complex yet not overly complicated wines. Advocates use a food metaphor, like homemade vegetable soup, steel aged wine taste better when flavors are left on their own to combine, evolve & unfold. Steel aging produces wines with fruit forward aromas and a fresh, crisp taste.
Some winemakers choose steel aging due to their durability over wood which needs to be replaced every two-three years. The cost savings using steel over several years to investing in wooden barrels costing up to $2,000.00 each are notable.
The opposite from steel, wood fermentation and aging affect the wine’s taste & mouth feel, adding aromas, tannins and textures. The Romans adopted wooden barrels for easier transportation than clay amphorae. Wooden barrels are porous, exposing the inside to outside air, allowing wine to slowly breathe or oxygenate. Smoothing, softening or “rounding out” wine, the evaporation concentrates flavors or mouth feel.
Oak the wood of choice, stores liquid without resin or sap residue and strong yet pliable enough to form a barrel. Oak aged wines impart a creamy texture from Malolactic, secondary fermentation, distinct aromas, and plethora of tastes; caramel, cinnamon, coconut, marshmallow, nutmeg, smoke & toasted bread. Oak can be new with strong flavors, or older and more nuanced. Charred or toasted the staves (vertical bands of wood) can be toasted lightly to densely charred imparting robust aromas & flavors.
United States oak is porous with pronounced aromas banana, coconut, even dill pickle. Highly regarded French oak with a solid grain is prized for producing wines with structured tannins and refined butterscotch, vanilla aromas. Slavonian oak is known for fruit & woody note aromas.
Short cuts to save time and money are increasingly common using oak staves, chips, powder even oak concentrate, i.e. liquid oak during fermentation and aging to adjust a wine’s character.