Growing & Winemaking


A Conversation with Aron Weinkauf

November 2017
by Laurie Daniel

Spottswoode Estate in St. Helena, Calif., is a Napa Valley classic: Wine grapes were first planted there in 1882. The current estate was established by Jack Novak and his wife, Mary, who started out as grapegrowers. Following her husband’s death, Mary Novak (who died last year) founded the current winery, 100 years after grapes had first been planted there. The collection of buildings dating from the 1880s exude a sense of history.

Spottswoode celebrates tradition, but it has not been bound by it. The winery has been an innovator over the years. The Novak family has farmed the estate vineyard organically since 1985, and it was certified in 1992. More recently, Biodynamic practices have been introduced. The winery recently has been renovated, and state-of-the-art equipment has been added.

Supervising both vineyard and winemaking is Aron Weinkauf, who has been with Spottswoode since 2006, when he became assistant winemaker under Jennifer Williams. Weinkauf, who graduated in 1999 from Berry College in Georgia with a degree in Spanish, developed an appreciation for wine while studying in Spain. When he returned to the states, Weinkauf enrolled in the viticulture and enology program at California State University, Fresno, and graduated in 2005. He worked at Ficklin Vineyards and Paul Hobbs before joining Spottswoode.

Weinkauf developed a deeper interest in viticulture at Spottswoode, and he became vineyard manager (in addition to his winemaking duties) in 2009. Two years later, he became the fifth head winemaker in Spotts-woode’s history.

Q: You’ve been using an optical sorter for several years. What are the advantages? Has it improved quality? Are there any disadvantages to using it?
Aron Weinkauf: We began using a state-of-the-art Weco Optical Sorter in 2014. Historically at Spotts-woode, sorting was a very slow, very labor-intensive process that required 10 people standing on a sorting line to process approximately 1.4 tons an hour. With our new system, we can process 5.5 tons an hour with just four people working the sorting line. And because the machine does the lion’s share of the sorting, our team can focus on being even more exacting in their final sorting decisions.

There are many benefits to this approach: It allows us to keep the sorting day to a sane and safe six to seven hours for our team, and it frees up several team members, allowing them to focus their attention on other crucial areas such as analysis during harvest. And, if faced with heat events or the threat of rain, we are able to quickly process a much larger amount of fruit, with no sacrifice in terms of quality. In fact, the quality has been great. With three different cameras, including infrared, our optical sorter analyzes every berry to identify and eliminate unwanted grapes and plant material. We have also found that it rejects significantly less fruit, and yet it does this without sacrificing quality. When we were using manual sorting, a not-insignificant amount of great fruit would get discarded with lesser quality fruit, as some of the good would go out with the bad. That has been reduced by about a third. Since we’ve been using it, our optical sorter has met, or exceeded, all of our expectations. In terms of disadvantages, there are really none worth mentioning.

Q: Along with the optical sorter, you’ve started using a new destemmer. What have the advantages been?
Our Weco Optical Sorter was part of a complete upgrade to our grape-processing system, which also includes a Bucher Vaslin Oscillys and two shaker tables from Key Technology: one for cluster sorting and another for berry sorting. Beyond being able to process up to 5.5 tons per hour with far fewer people on the sorting line, these tools have other advantages: They are more precise, they reduce losses, and because we can use high-pressure equipment on them, they clean up quickly and easily, with a 40% to 50% water savings.

Q: Spottswoode recently renovated half the winery. What changes did you make?
While we did not change the footprint of the building, we renovated and modified over half of our tanks, with an increase in 2,000 gallons of tank holding. We also added a new control system. We replaced old cement tanks with three new stainless steel tanks that together have a capacity of 4,500 gallons. One of the tanks, which was made by JVNW, has extra insulation with multiple glass viewing ports down the side, which is great for R&D. We are able to look into the tank and view the actual fermentation to see what’s happening. We can see exactly what levels the cap and juice are at, and we can extract samples at specific levels to analyze what we are seeing. It is great for experimentation and analysis. We primarily use it for Cabernet Sauvignon, but we also use it for the other red Bordeaux varieties that we use for blending.

We also completely changed our glycol supply lines and ports. We used to have just one inlet, and we had to manually change the valving from the hot to cold cycle. Now it is all automatic, which provides more control and more precision. We also have a remote alarm system that automatically alerts us if something is not within our parameters. While we do not have remote monitoring yet, everything is digitized, and we find our alarm system to be sufficient. If something goes out of range, it will send us an email. This said, the system is entirely scalable, and we can upgrade our software to allow for remote monitoring at some point.

One of the things we love is having one touch-screen control panel for all our tanks, which integrates with all of our other systems. So, from a single location, we can see what is happening in our barrel room and other parts of the winery. Lewis Mechanical helped design and install the new system. While it is a custom system—and the first system of its type installed in the valley, with programmable elements that are unique to us—none of the main elements are proprietary. Any company we wish to work with can work on the equipment, and we can upgrade software easily. In terms of what makes it unique, we have one main control panel that links to all of our tanks and barrel rooms. We have automatic valves so we can tell a tank to heat automatically from one interface; and our hot glycol is now digital.

Q: You’re running trials involving a couple types of concrete eggs as well as a ceramic e gg. What have the results been?
We have been running Sauvignon Blanc trials using three different types of eggs for three years. It has been fascinating seeing the impact these vessels have on the wines and assessing what qualities they accentuate during the initial fermentation and, later, after months of aging in bottle. Interestingly, the initial characteristics often change dramatically after bottle aging, which is something we have learned to factor in for the final wines.

In broad strokes, we have found that each different vessel has its own signature impact on the wines. For instance, our ceramic egg from Vital Vessels yields wines with great balance and freshness that are more textured and showy in a very pleasing way. Our French Nomblot cement egg delivers a more mineral-driven wine with a hint of more reductive character. Our cement egg from Sonoma Cast Stone American falls somewhere in the middle in terms of results. It gives a little minerality, but it also yields a very clean, well-textured wine. Each is a great tool that provides something a little different in our spice rack. In terms of shape, size and coating, they are each somewhat different. The ceramic egg is 650 liters and has the classic egg shape that provides great natural convection. It is fired clay, which results in a very stable and inert surface. The French egg is 600 liters and is raw concrete inside, but it is a proprietary concrete blend. The American egg is fatter at the bottom and tighter at the top. It is our largest egg, at 1,800 liters, and its cement is mixed with other non-cement proprietary components.

In terms of pros and cons, there are a few things worth noting. Tartrate removal from the ceramic tank is easier than in the cement tanks, but the ceramic tank is a bit more delicate. From a winery aesthetics standpoint, the Sonoma Cast Stone allows you to have your logo done beautifully on the tank, and they come in different colors.

Q: With your winery lab, you’re able to do nearly all analysis in-house. How has that changed the way you do things?
We built our winery laboratory six years ago, and it has made a huge difference in our approach. The two key pieces of equipment are a Mettle Toledo Titrater and an Astoria-Pacific Discrete Analyzer, which does automated enzymatic analysis. Together, these tools dramatically cut our analysis costs and the time it takes to get data back. In the past, we had to send out analysis, and it was expensive. Now we can do analysis on every single barrel and tank, and it is much more focused and precise. This allows us to manage every single fermentation in 21 tanks and as many as 250 barrels each vintage, with barrel-by-barrel analysis, where we can monitor for complete fermentations, glucose/fructose, malics, VA and individual sulfurs. This has been hugely beneficial for overall quality, and the cost savings paid for the equipment in just a few years. In fact, our ROI on all of our new equipment has been from one to three years.

There are few things that we still need to send out for lab work for a variety of reasons. We do not have a machine to measure alcohols, which is something we usually only check once, since after we check it, the levels tend to be very stable. The machine for analyzing alcohols is very expensive, and the ROI just didn’t make sense based on how often it would get used. We also choose to send out our juice panels, since that is a relatively inexpensive analysis that can give us 10 to 12 different variables all at once, and we send out for microbiology. The other things we send out are things that have to be certified by a third party for export. For instance, we have what we call our Pacific Rim Export Panel and our Canadian Export Panel. Some of the things that these panels certify we can actually do in-house, but we need the legal certification from outside laboratories to sell our products in these markets.

Q: You’re using mobile services for bottling and cross-flow filtration. What are the advantages? Are there disadvantages?
The advantage of using a mobile service is that you are using state-of-the-art, perfectly maintained equipment run by professional technicians who know the machines inside and out, as opposed to people who may only do bottling once or twice a year. The disadvantage is scheduling. With mobile services, you have to work on scheduling and availability in advance, which leaves less flexibility if you need to change your bottling dates. As far as cross-flow goes, we like the quality of the filtration that we get at lower pressures. For our bottling, we have been working with a great company called Ryan Mobile Bottling for almost 25 years, and we use Juclas USA for our filtration.

A resident of the Santa Cruz Mountains, Laurie Daniel has been a journalist for more than 35 years. She has been writing about wine for publications for more than 21 years and has been a Wines & Vines contributor since 2006.

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