Skip to main content Skip to navigation

Undergrad Researcher Experiments with Co-fermentation

Scholarship helps fund project

Undergraduate student Landon Keirsey interned this summer at Double Canyon Vineyard in the Horse Heaven Hills AVA near Alderdale.
Undergraduate student Landon Keirsey interned this summer at Double Canyon Vineyard in the Horse Heaven Hills AVA near Alderdale.

The synergy created by co-fermenting black and white grapes together can create a truly wonderful wine. The winemakers of France’s Rhone Valley, where Syrah and Viognier have long been fermented together, are masters of this style of winemaking.

Unlike the more common art of blending already fermented wines, co-fermentation raises many questions. Do white grapes, for instance, dilute the color of black ones when added to a co-fermentation? And what about the aroma of a co-fermented wine? Is it the Viognier grapes that lend the wines of the Rhône Valley’s Côte Rôtie appellation their aromatic qualities?

These and other questions are being researched by WSU viticulture and enology undergraduate Landon Keirsey and his faculty advisor, James Harbertson. Harbertson is an enologist based at WSU’s Irrigated Agriculture Research and Extension Center in Prosser and a designer of WSU’s research winery in Prosser.
This fall, and funded in part by a grant from the Rhone Rangers, Keirsey will make co-fermented wines in small batches at the research winery. The wines will be made with varying amounts of Viognier grapes and compared to two control wines, one made solely with Viognier, the other with only Syrah grapes.

Using sophisticated scientific techniques, Keirsey and Harbertson will analyze the aroma, color and tannin compounds in the wine. Keirsey hopes his research will be useful to winemakers, especially as Rhône-style wines become more important in the marketplace.

“I wanted to conduct this research because it’s important for winemakers to have hard data to reinforce their practices. It’s also a great opportunity for me to learn and get some experience doing science,” said Keirsey.

“The great thing about having the research winery is that it lets us answer so many questions important to industry,” said Harbertson. “It also gives undergraduate researchers a chance to get experience that reinforces their classroom learning and that gives them a leg up in terms of experience when they go looking for a job.”