Winemakers Explore Aeriel Imaging, Fermentation Vessel Choice During Oregon Wine Symposium
February 26, 2015
There were two programs of special interest at the Oregon Wine Symposium held at the Convention Center in Portland on February 26, 2015.
The first was titled “Spectral Aerial Imagery: An In Depth Look at a Precision Farming Tool to Support Zonal Management” presented by Susan Ustin (UC Davis), Rob Sorenson (Senior Viticulture Manager, Wente Family Estates), and Chad Vargas (Vineyard Manager at Adelsheim Vineyard).
The panel described the different types of aerial imagery available to vineyard owners and managers: satellite, Sky Box imaging services offered by Google, Higher Revisit imaging services, TerrAvion services, which is coming to Oregon in 2015 (This service offers a subscription for 40 weeks of flights), and finally unmanned aerial vehicles (UAVs) or drones, which are low cost flights that offer higher resolution because of their lower flight altitude. Preliminary FAA rules on use of drones were recently released).
Susan Ustin of UC Davis discussed how a vineyard owner should manage remote sensing, noting that plant-based sensors can’t be automated, and meteorological sensors installed around the vineyard can leave a big footprint. Aerial imagery, on the other hand, can display plant vigor, and show the entire vineyard. There is less energy in water stressed situations. The aerial maps are correlated to water returned. Leaking of irrigation systems can be seen clearly.
Rob Sorenson, Senior Viticulturist for Wente Vineyards spoke about his experience with aerial imagery. He said it is useful to see the vineyards from 10,000 feet. In 2014 Wente obtained more than 30 images during the growing season. Images are electronically distributed and are in color and high resolution.
Aerial imagery is useful for harvest planning, irrigation decisions and data collection about the crop. Harvesting decisions can be based on individual block information to increase wine quality. One drawback, said Sorenson, is that properly interpreting the data can be challenging, and depending on the quality of the data there is room for error.
Are smaller fermentation vessels better?
A second program titled “Fermentation is As Fermentation Does: Fermentation Vessel Considerations.” featured Don Crank (Willamette Vineyards), Isabelle Meunier (Isabelle Meunier Consulting), and Andrew Beckham (Beckham Family Estate).
Don Crank, Head Winemaker at Willamette Valley Vineyards discussed the pros and cons of giant, durable temperature controlled tanks, saying they can give an almost carbonic feel to the wines. He now prefers smaller tanks with open top lid; the lids actually float on the top.
Isabelle Meunier, the winemaker at Lavinea Winery (she was the former winemaker at Evening Land) spoke about wooden vats with plastic liners and about concrete vats. Meunier espoused the belief that smaller is better. Her maintenance regime for the wooden vats includes rinsing and regular SO2 applications to protect against mold.
Concrete vats come in different shapes, but Meunier prefers to use the same shapes as the wooden vats. Both types of vats are both fully open at the top and require a lot of space. Meunier first seasons the concrete vats with tartaric acid before use. She noted that the vats are quite porous, and stated that while exposure to oxygen during fermentation may be good, it is less than ideal when working with a finished wine.
Choice of vessel can depend on winemaking technique. Meunier said oak vats can accomodate higher fermentation temperatures than concrete and that a winemaker can get more tannin extraction with a higher fermentation temperature, in addition to more complex flavors and less primary fruit. Meunier said desired wine style and economics should dictate a winemaker’s fermentation vessel choices.
Andrew Beckham, winemaker of Beckham Family Estates, was a potter before he became a winemaker, so he makes the amphorae he likes to use for making wine. Becker first lines his amphore with beeswax or soy wax, then seasons them using a 30 percent tartaric acid. If later there are any microbial issues, he can clean the vessels by putting them back in his kiln. Stainless steel lids are attached to the amphorae. Becker did note that amphorae take up a great deal of space in the winery. He makes them in sizes of 90-200 gallons, and can use them for multiple years.