Though whole cluster fermentation is not a new winemaking technique — and was, in fact, the primary way of making wine for centuries before modern winemaking machinery — the average wine-drinker today is unfamiliar with this unique method. How is whole cluster fermentation different than any other kind of fermentation process, and in what ways does it influence a wine’s flavor?
Whole cluster fermentation is really no different than it sounds: the whole grape cluster is kept intact when harvested off the vine, then crushed and fermented with its stems included (versus the more conventional method, in which clusters are de-stemmed prior to fermentation). Though it’s typically used with Pinot Noir grapes, whole cluster fermentation can also be seen with varietals like Grenache and Syrah — there are no rules!
Stem inclusion brings a number of interesting characteristics to the wine. Some people notice structure, spice, and tannic qualities that are typical of wines having undergone whole cluster fermentation. Notes of black tea, fresh herbs, and ripe fruit are also common. By fermenting grapes with their stems and all, the wine might also give off more place-specific traits, allowing you to better “taste” a particular vineyard, appellation, region, etc.
At Carr Winery, whole cluster fermentation starts with carefully handpicking the grapes so as not to break or damage the fruit. Keeping the stems and grape skins intact allows fermentation to occur inside the grape itself. As yeast penetrates the skin of the grape, the juice inside ferments, causing pressure to build until the fruit bursts. It’s a fine-tuned process that results in a delicate, well-balanced wine.
This year, we released our 2017 Carr Whole Cluster Grenache from Kærskov Vineyard in the Los Olivos District, adding it to our lineup of whole cluster wines. At just 50 cases produced, this single-vineyard Grenache is not to be missed — and don’t forget to explain your newfound knowledge of whole cluster fermentation to whoever you share it with!