Twelve months of work in the Russian River Valley lead to one magic moment for winemaker Fred Scherrer: The day when Pinot Noir arrives at the Scherrer Winery. Fred says that “Pinot Noirs are typically destemmed, but not crushed; fermented in simple open-top fermenters; and manually punched down.” (link to their page and this quote here: https://scherrerwinery.com/pinot-noir/)
The choices Fred makes at the winery on this critical day are the result of a lifetime of experience working with Pinot Noir in Sonoma County. We asked him to share a guide to making wine so that we might better understand this complex and wonderful process.
HOW TO MAKE WINE: Fred Scherrer’s Guide to Using a Sorting Table and Destemmer
STEP 1: Preparing the Grapes
After harvest, the grape bunches are placed on a sorting table above the destemmer. This is used to control the rate at which the grapes fall into the destemmer and allows the winemaking team to pull out any leaves or rotten berries that made it in from the vineyard.
The destemmer is essentially a horizontal basket with holes in it, and inside is a finger-like auger that flops the grapes around gently between each other. As they bump against each other, the grapes detach from the stems and fall through the holes into a catch bin below.
STEP 2: Adjusting the Destemmer
To ensure that the grapes are destemmed correctly, Fred is careful to adjust the speed at which the machine runs. If the speed is too fast, he risks breaking the stems and getting unwanted pieces into the fermenting tank. If it's too slow, he may not detach all the grapes which reduces yield and wastes all the effort made to grow this Pinot Noir. Like almost everything Fred does at the winery, he finds it's best to move slowly and deliberately when working with Pinot Noir.
STEP 3: Transferring the Grapes to the Fermentation Tank
Once the grapes have been destemmed, they fall into the catch bin, which Fred picks up and empties with a forklift. Some larger wineries use pumps and other mechanical processes to transfer grapes from the bins to the tank, Fred relies on gravity, lifting the bin above each tank and slowly pouring it into the fermentation vessels. He feels that it's best not to pump anything that has skins on it because it may grind up those solid bits of grapes more than desired, leading to rough and unwanted tannins in the final wine.
STEP 4: Liberating the Juice
In the process of destemming the grapes and transferring them to the fermenters, Fred finds he usually has free juice that covers the mass of grapes all the way to the top. If not, he’ll ask to have someone jump in with brand new clean rubber boots and walk on the grapes a little bit to liberate a bit more juice. This way, he doesn’t have a lot of air space between grapes which is critical because an interface between juicy grapes and the air is a perfect opportunity for unwanted microbes to grow. Much of the microbial growth that can occur in the first few days is not necessarily part of what he wants to happen. Fred like to have a more controlled environment where you can see the entire surface or interface right on the very surface of the fermentation tank. If something starts growing that he doesn’t want, it’s right there on top of the tank for him to see and correct.
STEP 5: Cooling the Grapes
If the grapes are harvested on a warm day and come in hotter than he wants, Fred will put a slotted screen down inside the mass and then pump it through a heat exchanger to gradually cool the entire mass. This is not exactly a cold soak, which is sometimes used to extract more color from grapes, he just wants to delay biological activity in the fermenter.
STEP 6: Using a CO2 Snow Cone
A CO2 “snow cone” is used to create a very cold vapor of CO2 that hovers over the grapes. The carbon dioxide sublimates and the stuff is so light that it's actually hovering and kind of floating over the surface. This removes all or the majority of the oxygen away from the surface of the juice. Fred then put a tarp over it to hold the carbon dioxide environment there, which further delays biological activity.
Of course, this is just day one. Many more steps follow, and Fred will let the young Pinot Noir rest in a barrel for two years before bottling, and then another few years before release. Unlike almost any other producer in the Russian River Valley (or anywhere else in the world, for that matter) Fred releases his wine to the wholesale trade when he finds them to be ready to drink in a restaurant. This usually means that a Scherrer Winery Russian River Valley Pinot Noir sold at Candid Wines in Chicago will be somewhere between six to eight years old!
Interested to know more:
Dr. Jaime Goode of the Wine Anorak takes a deep dive into Whole Bunch fermentations and winemakers’ thoughts on destemming: https://www.wineanorak.com/wholebunch.htm