Wine is a living product
This was my submission for the August 2022 SommJournal essay contest. The prompt was, "How does aging in oak or stainless impact a finished wine?" My entry was not selected as the final award; however, I was happy to incorporate the recent online masterclass I had the pleasure of attending with Olivier Bernard of Domaine de Chevalier.
Wine is a living product. Each vintage is a snapshot of harvest: sugars, acids, and phenolic contents achieve balance dictated by growing conditions. The art of expressing terroir lies in capturing this picture in as short as four months or as long as twenty-four (or longer), and hoping it continues to gracefully develop for decades in bottle. To get from grape to glass, the winemaker’s most impactful decision is the vessel’s material selection, which will either retain characteristics of the fruit or develop them. As climate change alters the conditions in winegrowing regions, warmer vintages will see a shift towards inert vessels like stainless steel or larger oak to retain freshness and balance.
The impact of the vessel on the finished wine ranges from inert (low-impact) like stainless steel or glass-lined cement to oxidative (high-impact) found in small oak barrels. A winemaker wishing to capture acidity and freshness will opt for inert vessels. Here, the tank preserves the balance at harvest and simply allows the wine to clarify. Stainless steel also has the benefit of better temperature control during fermentation, which in the case of youthful wines meant to be consumed within a few years is paramount. That is not to say that it is impossible to control fermentation temperature in oak, but it is more difficult.
If the fruit requires maturing, such as polymerizing of tannins, oxidative vessels are the better choice, such as in Bordeaux and Napa. There is also a unique interaction of oak and ester development during fermentation, which is why many premium red wine producers take on the arduous task of fermenting in open top barrels. Additionally, oak barrels have been shown to reduce vegetative aromas and enhance fruitiness, helping offset negative characters in cooler vintages; however, as understanding of these compounds evolves, growers have more options in vineyard practices to better ripen fruit. As climate change continues, at what point is too ripe?
Today, winemakers have the greatest flexibility in how to age their wines, given local regulations or traditions (I doubt we will ever see Grand Vins of Bordeaux eschewing new barrique nor Barolo lessening aging requirements). As temperatures climb, ensuring wines retain freshness and balance will steer winemakers to using more inert vessels to preserve the acidity of the harvest in the finished wines. That is not to say that all previous oak-aged wines will convert to stainless, but we may begin seeing wines finish their elevage in tank rather than barrel, as Olivier Bernard of Domaine de Chevalier does for his Sauternes. For Bernard, capturing the precision of harvest is paramount. “Precision of the fruit. Precision of the aromatics. That is Sauternes.” Today, he is experimenting with oak casks up to 1500L, more than six times greater than traditional barrique. Other like-minded vignerons around the globe will be looking towards larger format oak and inert vessels to ensure balance of their wines, expression of terroir, and delicious wines to enjoy for years.
Eric Taylor
Advanced Sommelier
July 29th, 2022