The Science of Silver Oak
Together with her Alexander Valley counterpart, Laura Oskwarek helps translate and execute the overall style for our Cabernets. But beyond making sure that what goes in the bottle lives up to the promise of Silver Oak, both winemakers conduct experiments using leading edge technologies that help push the quality of our Cabernets forward. They help identify areas for exploration, draft hypotheses, design experiments and analyze results—and that’s just for starters.
Remote Work
In October 2019, when only emergency personnel were provided passage through Healdsburg, former Silver Oak Alexander Valley winemaker Christiane Schleussner was at home on her couch—performing pumpovers at our winery. Thanks to an app that links directly to the winery’s power grid and cellar, she was able to remotely control the fermentation tanks that were filled with fruit from the recent harvest.
In the Lab
Christiane conceived a new process with Cork Supply in 2007 to improve corks in large format bottles. In contrast to our regular quality control process (where corks are randomly sampled, soaked in wine, smelled and discarded), the dry soak process is non-destructive and allows for individual cork sensory evaluation using water vapor pressure. “Being able to test each cork for TCA without destroying it has always been the holy grail,” said former winemaker Nate Weis. It detects TCA (2,4,6-trichloroanisole), the chemical compound that causes cork taint in wine closures.
In 2009, she presented the “dry cork sensory screening” process at the American Society for Enology and Viticulture National Conference, and the gamechanging breakthrough has been widely adopted across the wine industry. It has also given us one of the lowest cork taint rates across all bottle formats in the industry. Today, there are even several natural cork suppliers that offer a proprietary process—a development based upon Christiane’s research—and guarantee TCA-free closures.
It certainly feels satisfying to come full circle on something very important to the industry as a whole—and to have made a lasting contribution that benefits not only us, but also the entire field.
Christiane Schleussner, former Alexander Valley winemaker
In the Cellar
American oak is our gold standard and a signature of the Silver Oak winemaking style since the beginning—and Laura works closely with our cooperage, The Oak, in Higbee, Missouri. This hands-on approach presents us with an extraordinary opportunity to craft the best barrels to suit each of our Cabernet programs.
Being able to identify what we don’t like is almost more valuable than knowing what we do like. This is true of each round of experiments at The Oak, which informs us what to focus on—what to improve.
Laura Oskwarek, Director of Winemaking
Owning our own cooperage allows Laura and the winemaking team to experiment with critical variables like selection of wood, seasoning of the staves and toasting levels of the finished barrel. To best understand the nuances of American oak on a chemical level, the team then analyzes toasting markers in finished wines and rigorously evaluates their flavor profile and influence on the wine.
In the Vineyard
The role of the production winemaker also extends to the vineyard and enology lab. In 2019, Laura helped design and implement an irrigation trial of Cabernet Franc. This data set benefits the vineyard team, as they know how far to push water stress without impacting long term vine performance. But the learning doesn’t end there. Laura and the team are planning future trials to look closer at the variable of time—and whether there are long-term effects on the vines.
If you’ve ever wondered what it’s like to be a Silver Oak winemaker, know that they’re life-long students. Their curiosity made them a better leader, and they continue to challenge theories and themselves vintage after vintage.