It’s harvest time, and one big question many winemakers have is whether to use stems in their wines, or not! This week, we borrowed a little commentary from Jordan Mackay, our Inside Source Editor and Inside Source Wine Club Writer, on this fun topic for #SciFri. “To rile up a Pinot Noir producer you need only mention two simple words: “whole cluster.” With Pavlovian reliability, the phrase will send them into one of two states: orgasmic bliss or black rage.
To destem the grapes or ferment whole cluster on the stems is the first important decision a producer will face beyond the vineyard. Most producers in North America are content to destem and make lovely, fruity Pinot Noir. A few, however, are brave enough to include the dangerous stems in the must, chancing the inexcusable green flavors that can result in pursuit of something more complex and unique. It is undoubtedly a high-risk gambit. Whether it is high reward is something that winemakers continue to dispute.
The problem is that no one seems to have a good answer. Theories abound but, as with so many aspects of the production of wine, the variables involved seem almost infinite. Supporters of destemming have their own Burgundian superhero to pit against the likes of Dujac and DRC: Henri Jayer.
While no one exactly knows the benefits of whole cluster fermentation, some of it has been observed and agreed upon. The first is that it prolongs the fermentation. Pinot Noir is a particularly fast fermenter that seems like it can go dry in a day. And it has low anthocyanins, so you have a color issue and an extraction issue if your fermentation goes too quickly. One way to deal with that is the Burgundian trick is to leave the fruit on the stems, not crushing it, which take longer to get going and stretches the fermentation length.
Another benefit of stems could be that they actually contribute to mix. For one, they have tannin—tannin that Pinot Noir grapes don’t have. Stems can possibly fill out the tannin profile of the wine and lead to lacier, broader mouthfeel.
Finally, taste. If they don’t provide green flavor, the stems can add beautiful notes of spice, herbs, pepper, and live vegetation. They can make a simple wine far more fascinating.” – Jordan Mackay
Photo, hands and Pinot Noir clusters courtesy of our good friend Drake Whitcraft who said, “Pretty little thangs ain’t they?” Yes, they are, and Drake does whole cluster 🙂