A Quick Guide to Stainless Steel in Winemaking

Stainless steel tanks aren’t as sexy as oak barrels or clay amphoras, yet they’re the essential tool for modern winemaking. 

In the grand scheme of things, stainless steel is brand new to winemaking. It first emerged in the 1950s, becoming essential for today’s winemakers. Many varietals and regions rely solely on this method for producing wines with a level of precision that was previously impossible.

In this post, I’ll break down the history and purpose of using stainless steel in winemaking, as well as notable varieties and styles that have built their reputation on this modern tool.

According to the Blooming Grape, Californian and select European winemakers first implemented stainless steel in winemaking in the 1950s. By the 60s and 70s, it was commonplace. 

Today, using stainless steel to make wine is virtually a given, and it’s used throughout the process. Whole grapes and freshly pressed juice are often stored in tanks before being racked into barrels–a process also referred to as “barrel downs.”

Once the wine is considered finished (fully fermented, dry, and delicious), it’s racked back into tanks for blending and bottling. Winemakers may also choose to ferment wine in tanks without ever touching a barrel if they want to preserve the wine’s nuances or minimize added flavors and aromas from oak. 

Much like oak barrels, there is a big difference between storing a finished wine in tanks versus fermenting in tanks. Any wine can be aged in oak and then transferred to tanks, and you’d never be able to tell. 

Fermenting is a different story since the omission of oak drastically changes the flavor, aroma, and texture of wine. Make sure to read my guide on oak barrels for more on the subject.

Tanks can be sealed airtight, whereas barrels and concrete eggs are not. This allows for an oxygen-free environment where the winemaker has complete control over the juice. Minimizing oxidation helps preserve fresh, crisp fruit flavors and aromas. 

In addition, tanks can also be jacketed or cooled via a glycol system to keep the fermenting grapes from overheating and developing flaws.

Because we have an airtight seal and zero oak influence, you will only taste the precise flavors of the grape. Stainless steel is also easier to clean, so you can maintain a sterile surface that’s unlikely to develop any “off” flavors from unwanted bacteria.

As mentioned, tanks are ideal for storing large quantities of wine and or unfermented juice. They’re also cheaper than oak, and you can use them indefinitely. This means you can store fully finished wine virtually forever, so long as it’s deprived of oxygen.

If you’ve ever had a cheap bottle of red and thought, “Wow, this tastes really smooth!” that’s no accident. Bulk wine producers rarely age or store wine in oak barrels due to the cost and labor required. 

Instead, they ferment in tanks and then add oak flavor in the form of oak chips or oak extract. This gives the wine its roundness and full body, minus the added cost and labor of oak barrels.

• Chablis – A white winemaking region in Burgundy that specializes in stainless steel Chardonnay. These wines are rich with white flowers, citrus, and mineral elements you only find in high-quality, unoaked Chardonnay.

• Prosecco – An Italian sparkling wine prized for its big bubbles, zesty flavor, and affordability. Prosecco is made using the Charmat method, AKA the tank method, where sugar is added to white wine in tanks, then sealed shut until bubbles form via secondary fermentation.

• Vermentino – Popular in Sardinia, Italy, Vermentino is almost always made in stainless steel tanks to preserve its bright, fruity flavor.

• Beaujolais Nouveau – One of the few red wines that is commonly made using the “carbonic maceration” method, where whole grapes are sealed in tanks and burst as the pressure builds. This preserves the subtle tannins and delicate fruity elements of the wine so it isn’t overpowered by excessive oak.