For the last few years we’ve quietly worked egg-shaped concrete fermentation tanks into our regimine of stainless steel tanks, oak vats and plastic T-bins. These UFOs (unidentified fermentation objects) draw lots of stares from visitors but they are now a fixture in the winery; they’ve been fully assimilated. What gives?
The story goes all the way back to ancient Greece (yes, we’re going there, but only for a minute) where wine was fermented in ceramic urns or amphorae. While there are no Parker scores for Etruscan Cabernet ‒ the vintage being 800 B.C. after all ‒ we do know that the wines of the era were highly prized and widely traded.
Fast forward to the mid-twentieth century and many European wines are still being made in concrete tanks. But along the way, oak was “discovered” and it did something concrete fermenters did not: it imparted flavor ‒ a whole spice-rack’s worth. By the early 80s, stainless steel became the preferred fermentation vessel as wineries sought a “fresher” style of wine.
But times change, techniques advance, and of course, winemakers want new toys. Thus concrete made its comeback, this time in the shape of an egg. The benefits are many:
Concrete “breathes” like oak, but leaves no flavor behind, like stainless steel. It preserves the grape’s fruit quality during fermentation. That’s because concrete has millions of microscopic pockets that are refilled with air each time the tank is emptied. These tiny voids of oxygen help to preserve aromatics, tame tannins and improve mouthfeel.
Concrete tanks ‒ whose walls can be up to six inches thick ‒ provide natural insulation from outside temperature swings that stainless steel tanks cannot without jackets and coolants.
Concrete is more cost-effective over the long term. When you consider what a new oak barrel costs, how long its useful life is, and how many a winery uses, concrete makes a whole lotta sense. Concrete lasts for decades. Generations, even.
So, strange as they may seem, concrete eggs are here to stay. At least here at Reynolds Family. Nanu-nanu