Oak barrels are not the only holding tanks you’ll find onsite at a wine cellar. Some wines are not meant to absorb the woody elements extracted from the barrel and thus the winemaker’s choice as an alternative is stainless steel. This durable metal is used by the wine industry largely because it is neutral — it neither adds nor takes away aromatic nor flavor components from the juice as it becomes wine.
Stainless steel was developed in England by a metallurgist named Harry Brearley at the beginning of the 20th century to serve the military as a rust resistant element in the making of munitions. Once perfected, it was adopted by a wide range of industries. It is believed that the first tanks were installed in a brewery in 1928. Stainless steel was then introduced to the wine industry in the 1950s for fermenting, aging and storage purposes.
Beyond its neutrality, stainless is very low maintenance: it is non-toxic, rust-resistant, and zinc and lead-free. It is easy to keep clean especially (vis a vis oak barrels) and gives winemakers control over the fermentation process by limiting wine losses and reducing the wine’s access to oxygen as happens when wine is stored in porous oak barrels.
In the modern era, most tanks can also have “jackets,” through which cooling agents flow to aid in temperature control during the fermentation process, which is especially important in the production of whites which must be kept cool to preserve their delicate fruit aromas and flavor profiles. And as mentioned above, stainless will not impart any elements which effect on the taste or aromas of the wine.
Stainless is also very durable. It is actually “self-healing.” If the tank is ever scratched, the oxide film regenerates and essentially seals the blemish, preventing corrosion.
Most tanks are custom made to winery specifications. Cellar ceiling heights, winemakers’ skill — one 2,000 gallon tank of flawed wine can ruin a business, so many new wineries look for smaller tank — the available of capital — tanks are expensive, from $5 to well over $10 per gallon of storage — and the quantity of each variety of fruit available from estate vineyards determine whether a small tank of 250 gallons or a huge one of 25,000 gallons is appropriate to the vintners’ needs.
Clean out ports on the large tanks, big enough for the resident “cellar rat” to climb inside with a scrub brush and high pressure hose, valves to match pumps that move wine from tank to tank, a flat or V-shaped bottom, “punch down” plates, internal paddles for mixing and many other options are usually designed by winemakers to meet their very unique needs.
Though the initial investment in a stainless steel tank might be daunting, the long-term investment is well worth the initial expenditure. When properly maintained, these tanks will last almost indefinitely.
Stainless is also versatile: it can be used for fermenting, aging, blending, bottling, short-term holding — before certain wines are transferred to oak barrels — and long-term storage.
Stainless is especially important in a region like ours that focuses, to a large degree, on cool-climate whites. For example, a Pinot Grigio might start out in an oak barrel, but will likely spend the majority of its time in stainless steel where factors like temperature are easily controlled and the fruit flavors and aromas remain true to the grape variety.
Even chardonnay, which often can be “oaked,” would become undrinkable if it spent its entire life in oak barrels. For cool-climate whites, our vintners generally look to create a finished product that shows lots of fresh, fruity aromas and has a clean, crisp finish – and for those attributes, stainless steel tanks are critical.
DONNIELLA WINCHELL is the executive director of the Ohio Wine Producers Association. She can be reached at dwinchell@OhioWInes.org.