Science in Paradise, Upcoming Events, Wine Cruise

Doing Science in a Phenolic Paradise

Federico Cassasa extends his phenolically enhanced hand. The day we talked, he had been busy crushing red wine grapes. For a few days or weeks each fall, winemakers walk around with purple hands.
Federico Cassasa extends his phenolically enhanced hand. The day we talked, he had been busy crushing red wine grapes. For a few days or weeks each fall, winemakers walk around with purple hands. Photo by Brian Clark, WSU MNEC.

“My main interest is in the kinetics and extraction patterns of phenolics during the maceration process of red winemaking,” Federico Casassa told me when I caught up with the doctoral candidate at Washington State University’s Irrigated Agriculture Research and Extension Center in Prosser. It took me a minute to mentally unpack that statement, yet that single sentence may hold not just a doctoral dissertation but, potentially, an entire career.

The phenolics Casassa refers to are a vast array of compounds responsible for the flavor, aroma, color, and mouth feel of wine. Maceration is the process of mixing and mashing crushed grapes and their juices, along with the grapes’ skins, seeds and stems until they up their phenolic compounds. Casassa and his mentor, enologist Jim Harbertson, are captivated by these alchemical compounds. Why? Because they are hoping to transmute purple jiuce into proverbial gold. As Casassa said, “If we can model how these compounds are extracted and interact with each other during maceration, then we should be able to make the wine we want, sensory-wise, based on what we already know about their sensory properties.

“In grapes,” Cassasa continued,”the phenolics are tucked away in cells. As long as they stay there, their behavior is, I would say, predictable. Once crushed, however, they are released and start interacting in very complex ways.” As the phenolics are released during crushing a wild molecular dance begins. Having escaped from their cellular confines, the compounds commence their kinetic conjuring act that results in the rubies of red wines and the golden pearls of whites. That, at least, it what it seems like to me. Fortunately for the winemaking industry, scientists like Harbertson, Casassa, and their research winemaker, Richard Larsen, put poetry to one side in favor of quantitative analysis.

Red wines are of particular interest to Cassasa because they contain a group of phenolics called anthocyanins. These are the compounds that give red wine its color and they are the primary focus of Casassa’s current research. He has isolated a number of anthocyanins from red grapes and shows that the color we perceive in red wine is in fact made up of a bunch of compounds that range from pale pink to deep purple. He carefully pours out tiny beakers full of the different anthocyanins he has so laboriously extracted. “This stuff is like gold to us,” he said. He’s been able to analyze the juice from red wine grapes to see how much of each anthocyanin is present but, he adds, “different grapes have different proportions and, on the top of that, the way you conduct maceration plays a huge role as well.”

When I asked him why he is here, doing this research. Casassa explained that he considers himself a winemaker first. Indeed, on the day I spoke with him, he, Larsen and Harbertson had just finished crushing a small mountain of grapes, and their hands were stained purple.

Mmm, anthrocyanins. The peaks on the graph indicate their relative concentrations in the particular grape he painstakingly extracted them fron.
Mmm, anthrocyanins. The peaks on the graph indicate the relative concentrations of anthrocyanins present in the particular grapes research Casassa painstakingly extracted them from. Photo by Brian Clark, WSU MNEC.

“I want my actions in the winery to be logical from a scientific standpoint,” Casassa said. “I want to be able to at least begin to explain why I am doing a particular thing in a particular way. It’s difficult, though, and maybe it’s impossible, but at the end of the day I think it is the thing that will make a difference.” He goes on to tell me something he heard a French wine scientist say: “The faster the scientific knowledge advances, the greater the risk of widening the gap between what we know and what we do.” The enological traditions, Casassa said, are not always supported by the enological science.

That, of course, is precisely the reason of viticulture and enology research programs, whether here in Prosser, at UC Davis where WSU scientists frequently find collaborators, or back in Mendoza, Argentina, from whence Casassa hails. “Brettanomyces was once considered part of terroir,” he pointed out, referring to a species of wild yeast that can infect wines and alter their flavor profile. “Now we know different: it’s just poor hygiene in the winery and lack of attention to the details of winemaking chemistry.”

Casassa worked in Mendoza as a research winemaker for Argentina’s equivalent of the USDA. “We made about 320 lots of wine a year and crush ran continuously from February until May. The climate is much milder there than it is here, and there are dozens of grape varieties grown in the area, so harvest went on and on.” He worked a harvest in France, too, before coming to the U.S. to work on his Ph.D.

“Washington is the most challenging place I’ve been, in terms of the chemistry of the fruit. The weather here is really extreme — the summer days are long but the growing season is short, very condensed. It’s fast and furious. There are places in Washington where, nearly side by side, you see varieties growing that, in Europe, would be hundreds of miles apart. Cold Creek vineyard, for instance, has Cabernet Sauvignon growing next to Riesling and they both excel there. That’s crazy!”

Casassa described the 2011 harvest at Cold Creek, near Matawa, as having “Wikipedia-perfect qualities” and “26 Brix.” It’s a beautiful thing, he said. “Washington is the perfect place to learn to be a winemaker because you encounter every sort of variation. Washington is a phenolic paradise.”

Brian Clark

For more information on winemaking research at WSU, please visit For more information about opportunities for graduate study in enology at WSU, please visit

Upcoming WSU Viticulture & Enology Events

Upcoming workshops and seminars
Upcoming workshops and seminars

Feb 21 – 22: “Spray Application Technology” with Dr. Michelle Moyer and Gwen Hoheisel. Presented at the WSU Irrigated Research & Extension Center, Prosser.

Feb 23: “Managing Disease According to Risk: The Tasmanian Experience” with Dr. Kate Evans, Tasmania, Australia; and “Blowing in the Wine: Inoculum Detection and Disease Management” with Dr. Walt Mahafe, USDA, ARS, Corvallis. Presented at WSU Tri-Cities, Richland.

March 22: “Wine Proteins: Yeast Contributions and Detection in Red Wine” with Dr. Alan Bakalinsky, Oregon State University, Corvallis. Presented at WSU Tri-Cities, Richland.

March 30: WSU Annual Viticulture and Enology Workshops. “Deacidification, How to Deal With Botrytis, Filtration, Winery Sanitation;” “Viticulture: Grape Vine Phenology, Disease Management;” and “Information Sources, How to Get the Best Out of the Information That You Have” with Drs. Michelle Moyer, Jim Harbertson, and Thomas Henick-Kling. Presented at the WSU Northwestern Washington Research and Extension Center in Mt. Vernon.

August 8: “Advanced Wine Analysis Workshop” with Dr. Jim Harbertson. Presented at WSU Tri-Cities, Richland.

August 15: “Wine Fault Protection: Acidity, White Wine Phenolics, and Pink/Brown Color” with Drs. Jim Harbertson, Richard Larsen, and Thomas Henick-Kling. Presented at WSU Tri-Cities, Richland.

April 13: “Vine-to-Wine Workshop” with Dr. Michelle Moyer, Gwen Hoheisel, and Drs. Jim Harbertson and Thomas Henick-Kling. Presented at WSU Tri-Cities, Richland.

Date to be determined: “Sparkling Wine Workshop” with Drs. Jim Harbertson and Thomas Henick-Kling. Presented in Woodinville.

For more information on any of these workshops, please contact Debbie Schwenson at 509-372-7224 or

For a complete listing of upcoming WSU viticulture and enology events, please visit

WSU Cougars Mediterranean Cruise

Cruise the Mediterranean with with wine experts in luxury.
Cruise the Mediterranean with wine experts in luxury.

Join world-renowned WSU Viticulture and Enology Director Thomas Henick-Kling, CAHNRS Dean Daniel Bernardo ‘85, and other WSU and Cougar wine community leaders as they sail the Mediterranean on a private Cougar-chartered cruise, May 28 – June 2, 2012. Embark from Nice, France, and call at Calvi, Portofino, Livorno, Portoferraio and Rome.

Special pricing for the first 42 cabins start at $2,450 pp. Proceeds will benefit the WSU Viticulture and Enology program.

WSU Cougars Cruise pricing includes:

  • All meals and snacks aboard ship
  • Special gourmet wine tasting dinners prepared by our celebrity chef
  • Featured wines served all day and evening throughout the cruise
  • Special WSU Cougars wine tasting events
  • Winemaker seminars
  • Educational seminars on wine, food, and ports of call
  • Special parties aboard ship
  • Two special WSU cocktail parties with complimentary drinks and appetizers
  • Live entertainment every night
  • 24-hour room service
  • Water sports at the Windsurf marina, including water skiing, sailing, and kayaking (weather permitting)
  • Airport transfers in Nice and Rome

Learn more at