EDITOR’S NOTE: This is the third part of a series of looking at the relationship of wine and wood. For past articles, visit lakewyliepilot.com.
It’s alive! Wine is a living thing.
Like a person it goes through stages in its life from conception to maturity. Its personality, like other living things, is a combination of its genetic makeup and the way it’s brought up, a combination of nature and nurture.
Wine starts its life in a vineyard. At just the right time, the grapes are harvested. They undergo a metamorphosis that transforms them into wine. The person with the task of nurturing this transformation is the winemaker. Like a parent, his or her decisions shape the future of the wine.
After harvest, the grapes go through fermentation. This is a process where the glucose and fructose sugars in the grapes are chemically altered by yeast to yield ethyl alcohol and carbon dioxide. Primary fermentation usually lasts about five to 14 days. Sometimes wine goes through a secondary fermentation further changing the wine. These fermentations usually last five to 10 days. Fermentation is a critical stage in the development of wine. Every nuance, such as temperature and type of yeast, will alter the wine. Everything is important, including the type of container or vessel the fermentation takes place in. To put it into perspective, think of the fermentation vessel as a “womb.”
Stainless steel tanks have long been used to ferment wine. At most wineries, you’ll see shiny stainless steel tanks. Stainless steel doesn’t breathe and is neutral in terms of imparting flavor to the wine. This works well with white wines that emphasize acidity. Wines such as Sauvignon Blanc often are fermented and aged totally in stainless steel. This promotes a crisp character and full-fruit flavors to the wine.
On the other hand, some white wines, such as Chardonnay, benefit from flavors imparted by oak. For this reason, fermentation of some wines are done in barrels. Wood is porous, and along with the oak influences, the wood allows the wine to develop softer, creamy flavors in the wine.
Red wines contains tannins, which give the wine color, flavor and structure. These tannins come from the stems, seeds and skins of the grapes. They also can come from wooden barrels. Tannins can be bitter but mellow out over time. Red wines don’t normally need additional tannins. White wines lack tannins and in some cases adding them can be beneficial. This is why most barrel fermentation is of white wine.
Everything old will be new again. Concrete has been around for a long time. The Romans used it to ferment and age wine 2,000 years ago. It’s also been widely used in South America and parts of Europe to make wine in more recent years. Until recently, concrete has been little used in wine production in the United States. That’s beginning to change.
A company in Petaluma, Calif., Sonoma Cast Stone, has begun producing wine fermentation vessels made of concrete. They make them in various sizes up to 1,000 gallons. What makes them unique is they’re egg shaped.
Concrete has advantages. It insulates well. It maintains consistent temperatures better than stainless steel, which is conductive. The egg shape allows for good fluid movement of the must inside and negates the need for stirring. Concrete also is easier to clean than wood. Concrete, like wood, is porous. It allows for oxygenation of the wine and being neutral, doesn’t impart flavor of its own into the wine. Some Napa Valley wineries including Caymus, Viader and Rudd have begun using concrete fermentation vessels and are reporting good results. They say the concrete gives richer, more supple flavors while maintaining aromas and enhancing texture. Several winemakers have remarked the eggs allow the “true nature” of the fruit to be expressed. This trend seems to be catching on along the West Coast and into Canada.
Who knows? Maybe the next bottle of wine you drink will have been born in concrete.
Jim and Marie Oskins live on Lake Wylie in Fort Mill. They can be reached at email@example.com.