Winemaking is often described as a delicate balance of art and science. Winemaker Theresa Heredia and Assistant Winemaker Brent McKoy share some of their “artistic” choices that result in wines of great elegance and balance in PART THREE (and the final segment) of this discussion...
Q: How do you decide which yeast strains to use to induce fermentation?
Yeast selection for white varietals is bit easier, as it is purely based on desired flavor and structure profile. Some yeast strains
produce more minerality and highlight citrus characters, while others produce fruity, tropical flavors. At Gary Farrell, we tend to select the strains that produce minerality.
While selecting yeast strains for red varietals is also based on desired flavor and structure profile, it has a lot to do with cellar logistics. To achieve a “pretty,” aromatic red, the choice is definitely a slow, cool fermenter. Many of the Russian River Selection Pinot Noirs are fermented with this type of yeast. The conundrum is that we often need to “flip” those tanks faster than the Single Vineyard Designate reds in order to create more tank space for new fruit coming in (multiple vineyards are often ready to harvest at the same time). For better tannin extraction, an aggressive fermenter works well. This type of yeast strain works well for many single vineyard reds, and since the fermentations go somewhat quickly, we have plenty of time for a long, extended maceration
Q: How do you manage the fermentation?
This part of winemaking would be very easy if we had a simple formula. However, this is not the case because we have a huge amount of diversity in our vineyards. And because not all grapes are the same, we must treat each fermentation differently. We tailor the number of macerations per day to the flavor and structure that we taste along the way, throughout the fermentation. This makes the winemaking process more fun and intimate.
That being said, there is a general protocol, which is as follows:
Q: What happens after the primary fermentation?
- After the cold soak, we allow the must to warm up and we add yeast.
- We do one punch-down per day until we see the Brix start to drop and the temperature rise slightly.
- During the beginning of fermentation, while it is still relatively cool, we might do one to two punch-downs per day.
- When the fermentation really starts to warm up, we’re at the critical extraction period. We usually do two to three punch-downs per day during this period, but it all depends on the flavor and structure desired. Sometimes we’ll replace a punch-down with a pump-over, sometimes we’ll do a combination of punch-downs and pump-overs, and occasionally we’ll do four punch-downs or a mixture thereof. There are also occasions in which we will opt to do only one punch-down per day during the peak of fermentation, if we taste and observe plenty of extraction naturally.
- We may add a random pump-over if the fermentation gets stinky from the sulfides (a binary compound of sulfur with another element or group).
- When the peak of fermentation is over, we generally drop down to one or two punch-downs per day.
- At the end of fermentation, we do a “wet cap” once every few days, to prevent the cap from drying out and also to prevent the proliferation of acetic acid bacteria in the cap.
- On a very rare occasion, we may opt to drain some juice from the tank and leave it separate overnight to encourage greater extraction in the main tank, then we’ll add it back the next day. This process is called delestage.
We like to do extended maceration on all reds, which can last from 5 to 14 days, but the duration depends on wine quality and tank availability for incoming vineyards.
Q: What happens during extended maceration?
We set the tank temperature to about 80-88°F. The temperature depends on a lot of factors, but the ideal temperature for this phase is about 83°F. The heat helps to fix color and build tannins. We taste each day during extended maceration, looking for improved flavor and tannin development. When improvements slow down or halt, we decide to drain the tanks and press immediately.
Q: Any final thoughts on The Art and Science of Winemaking?
What people may not realize is that in addition to art and science, operational constraints are also a key factor in our winemaking decisions. Science answers, "What do I need
to do?" Art answers, "What do I want
to do?" Operations answers, "What can
I do?" In a small cellar like ours at Gary Farrell, we must always be thinking five steps ahead to know how a current decision will play out later in the process. Winemakers need to have good palates, but they also need to be detail-oriented planners.