British Columbia Winemakers Talk Tannin
University describes new 'cheaper, easier' tannin assay coming soon
“I’m really happy to announce in advance—the master’s thesis will be defended soon—that we have a developed a new gelatin assay,” said Dr. Cédric Saucier, head of the chemistry department at the Okanagan campus of the University of British Columbia in Kelowna, B.C. “It will take three hours. It’s still a bit of time, but you will be able to run samples in parallel. It will just need wine, gelatin, test tubes, distilled water and a UV spectrometer—so no centrifuge.”
The assay arises from the thesis work of graduate student Dawn Visintainer, who is seeking a master’s degree at UBCO. Saucier told Wines & Vines he expects Visintainer to defend her thesis by September and, all going well, release a paper documenting the assay procedure soon after.
Preliminary results indicate the assay is reliable within 6%. Correlation of its results with those of the MCP and Adams-Harbertson assays is encouraging.
“It should be pretty similar type of results, but with an even cheaper, easier method,” Saucier said. “I cannot disclose all the procedures right now, but it’s going to be simple.”
The announcement comes as Saucier prepares to depart UBCO in September for a year’s leave—or longer—to head the enology program at the Université Montpellier II in Montpellier, France.
Saucier’s four years at UBCO have laid a respectable foundation for future enology research at the school, established in 2005 with the acquisition of the northern campus of Okanagan University College (now Okanagan College, based in Penticton).
Saucier secured $1 million worth of research grants for UBC-Okanagan, funding that supported work toward the discovery of 37 new wine grape molecules, including the identification of 23 previously unreported stilbenes in red wine. The newly identified stilbenes were reported in the Journal of Rapid Communication in Mass Spectrometry last week.
“We don’t know exactly the structure, we don’t know exactly what health effect they can have, but it’s huge!” he said. “All these compounds will generate a lot of studies.”
While leaving the door open to resuming his position at UBCO, Saucier appeared to be taking his departure for his native France in stride.
“It’s not the worst part of France,” he said, describing Montpellier for his audience. “It’s a few kilometres from the Mediterranean Sea.”
Saucier wasn’t the only person focussing on tannin at the conference.
Dr. Patrick Vuchot, who oversees research and development activities as director of the Institut Rhodanien in Orange, France, shared the results of work with consumers regarding tannins and tannin-enriched wines.
Two key points emerged.
On the one hand, researchers in France found that 41% of consumers enjoyed red wines whose tannins lent them a woody and astringent character.
The study used a wine that was 70% Grenache, 20% Syrah and 10% Carignan, prepared it according to four different winemaking techniques and then aged in four different manners.
But in a presentation earlier in the day, Vuchot noted that trying to select grapes for tannins with a view to the end product was a crapshoot. There are simply too many variables at play.
“Knowing the amount of tannin in the grapes isn’t enough for knowing the amount of tannin in the wine,” he said. “Even if you know the composition of the tannins, it’s hard to know how it will taste.”
B.C. isn’t the only part of the Northwest talking tannins this summer. Oregon winemakers will discuss tannin management “from vine to wine” at the Northwest Viticulture Center at Chemeketa Community College in Salem, Ore., on Aug. 7.