Stem research: is whole cluster fermentation the recipe for Pinot Noir?

Wines & Vines, Feb, 2005 by Jordan Mackay

Of course, the supporters of destemming have their own Burgundian superhero to pit against the likes of Dujac and DRC: Henri Jayer. Ted Lemon, co-owner and winemaker of Littorai and the first American ever hired as the winemaker for a Burgundian estate (Domaine Guy Roulot), remembers the legendary producer of Cros Parantoux and Richebourg once imploring "Stems, stems! Why would you ever use stems? We never have ripe stems in Burgundy!"

Thus, there in Burgundy, Pinot's holy land, the scales were forever balanced. Jayer vs. DRC. To destem or not. And still today in Burgundy, says John Haeger, author of the book North American Pinot Noir, "There's a lot of disagreement. If you could string the producers there in a line you'd probably get closer to 50-50."

In the U.S., of course, the percentage of whole cluster is much smaller. Jensen suggests that much of the California aversion to fermenting with stems (which, he says, he eventually discovered was high heresy at the enology department UC Davis), might have come from early attempts at Pinot-making in California.

"Often people didn't make the distinction between whole cluster and stem addition," says Jensen. "Producers in the '70s and '80s, thinking they were emulating Burgundy, would destem only to add the stems back into the must. But often they wouldn't have open-top fermenters and would have to pump over, which could only be possible if they chopped the stems up to be able to get them through the hoses. And if you chop them up, the results will be disgusting, as they often were. So people soured on the whole technique. Here at Calera, we treat the stems as gently as we treat the grapes."

While no one exactly knows the benefits of whole cluster fermentation, some of its merits have been observed and agreed upon. The first is that it prolongs the fermentation. "Pinot Noir is a particularly fast fermenter," says Joe Davis of Arcadian, a whole cluster practitioner. "It could go dry in a day. And it has low anthocyanins. Two of the five are missing, so you have a color issue and an extraction issue if your fermentation goes too quickly. One of the ways to increase extraction is to do a pre-fermentation maceration using dry ice and allowing that must to steep anywhere between two and five days. The other way to deal with that is the Burgundian trick of not crushing all the fruit to allow some of the intercellular activity to do separate little fermentations, which take longer to get going and stretches the fermentation length."

Steve Doerner of Cristom, who worked with Josh Jensen for 13 years at Calera, adds, "Whole cluster is the gentlest on the grapes. Nothing happens until the grapes are broken. It allows for a slow, long gradual fermentation. As we're punching down, we're breaking grapes slowly, and that slowness, I find, gives us that complexity."

The other benefit of stems could be what they actually contribute to the mix. For one, they have tannin--tannin that Pinot Noir grapes don't have. Larry Brooks, former winemaker at Acacia and now with his own Pinot house, Campion, notes that, "one of the things about Pinot Noir, when you analyze it in general, is that it has a preponderance of monomeric phenols, which are very bitter on the back of the tongue."