“The Aromas of Wine and Tea: a Sensory Adventure!” at the Global Tea Initiative, January 17 2020.

Note: all photos in this post are courtesy of Yan Chen, Yan Chen, Professor, Louisiana State University Agricultural Center Hammond Research Station.

Such fun to give the talk “The Aromas of Wine and Tea: a Sensory Adventure!”  with the help of Marzi Pecen. Here we are talking with attendees before the start—Marzi is standing on the right:

In the Sensory Theater of the Robert Mondavi Institute for Wine and Food Science we could have a true sensory adventure—we could experience directly how the aromas of wine and tea shift and change as we alternatively sniffed individual chemicals and the teas and wines.

Here’s a picture of the set-up:

In front of each participant were six cups (the wine glasses in the back were in place for Andrew Waterhouse’s talk about wine aging, that followed my talk). 

The three cups in front held (left to right) a green, oolong, and black tea, all Ready-to-Drink from Ito-En—thank you so much Rona Tison of Ito-En for providing these. The three cups behind the tea cups held a Chardonnay, a Pinto Noir, and a Cabernet Sauvignon, all from Robert Mondavi — many thanks to Babette Orendain of the Institute for the wines, and to her and her UC Davis student helpers for setting out everything!

(fBTW, the green tea was very close in color to the oolong—it was pan-fired—but it was clearly green tea by its aroma).

Earlier in the day, Colloquium speaker Susan Eberle, Professor (Chemist) of Viticulture and Enology, and Associate Dean, Undergraduate Academic Programs, College of Agricultural and Environmental Sciences at University of California Davis, had described some of the aroma chemicals common to tea and wine. Here is a picture of one of her slides:

To my great delight, I had chosen compounds that corresponded to these categories for my demonstration. I was planning to touch on all of these categories, but time was running short (we had to start late) so I chose just three:

• 2-phenylethanol, a phenylpropanoid, 
• β-damascenone, a C13-norisoprenoid,
• vanillin—note that vanillin is developed during the heating steps in tea and comes from the oak barrels for wine., so is not actually either in the grape or the fresh leaf to any extent.

We started by soaking perfume blotter paddles ("touches") then sniffing 2-phenylethanol and β-damascenone separately and then together. When we sniff them together our olfactory bulb joins them together as "odor objects" different from the two separate smells. For me and for many of the participants, the resulting odor object was "honey." However, people differ genetically in their ability to smell β-damascenone, so the "honey" effect was less pronounced for some. This observation allowed for a very short comment on the genetic ability to smell different aromas in teas and wines.

The next effect we experienced was masking. People first sniffed the Cabernet Sauvignon, then sniffed the 2-phenylethanol or the β-damascenone, then sniffed the wine again—the smell of the wine disappeared! The same held for the black tea. Neither the wine nor the tea has a significant amount of these compounds so, at the concentrations on the perfume paddles, these chemicals effectively masked the other aromas in the tea and wine.

By contrast, when we carried out the same experiment with the Pinot Noir and the Oolong, the aromas of each became richer and even more pleasant. This wine and this tea both have significant amounts of these chemicals; sniffing the paddles before sniffing the wine and tea brought out their aromas—an additive effect.

Vanillin is produced when oak barrels are fired, so oaked wines will have a lot of vanillin. The Chardonnay we had was only lightly oaked, so when sniffed alone if had a more fruity, less Chardonnay-like aroma that wasn't as pleasant as that of a more oaked wine would be—Andrew Waterhouse (Director of the Mondavi Institute) and I agreed that the wine had probably been treated with oak chips rather than been aged in a barrel. When you sniffed the wine after sniffing the vanillin, the aroma of the wine improved dramatically. 

Black tea is heated and fully oxidized, so it too contains significant quantities of vanillin, from the breakdown of lignin in the leaf's veins. Just as we experienced with the Chardonnay, the aroma of the black tea became richer after we had sniffed the vanillin. Interestingly, the vanillin somehow incorporated itself into the overall tea aroma, rather than stand out as separate but compatible as it did with the Chardonnay—with the black tea we were again experiencing odor object formation, which could be described simply as "black tea."

By contrast none of these compounds are present in green tea, so sniffing them before sniffing the green tea made the green tea either smell awful (for me) or just loose character completely (for some other people).

BTW, you can carry out some of these experiments at home with household herbs and spices. Will be live streaming to show how these experiments work on my upcoming twitch.tv channel. Details and link to come!

Or you could get samples of the actual chemicals in a Scents of Tea kit at http://scentsoftea.com and carry out the experiments with all manner of scents, wines, and teas.

==>> Now available on Amazon: Tea: a Nerd's Eye View.

5th Annual Colloquium of The Global Tea Initiative at UC Davis

Such fun at the 5th Annual Colloquium of the Global Tea Initiative—“Tea & Wine - The Great Debate”—at UC Davis under the leadership of Katharine Burnett!

Some highlights:

• People who know me know that I am not really fond of puer…but I was entranced by the dialog between Roy Fong of The Imperial Tea Court in San Francisco (https://www.imperialtea.com/Default.asp), and James Norwood Pratt, tea writer and connoisseur (https://jamesnorwoodpratt.com). Norwood asked the questions and Roy answered, all about how Roy produces his puers in his warehouse in San Francisco. He imports his raw maocha from China, then with a practiced eye for temperature and humidity at different levels in his warehouse, he moves his bings around to perfect them, for years and more years. It was an extraordinarily warm and friendly conversation that highlighted the cordiality that I find so refreshing in “tea people.” Am looking forward to a possible video of another dialog between these two, that my friend Marzi Pecen hopes to get off the ground.

• One persistent theme of the Colloquium was climate change and its effects on both wine and tea. The point about tea was forcefully brought out by Fitrio Ashardiono, Ph.D., Senior Researcher, Asia- Japan Research Institute, Ritsumeikan University, and UCD Visiting Scholar. His talk was entitled Tea Cultivation and Terroir Framework: Developing the Terroir Concept for the Tea Industry, but really focussed on how climate change would affect tea growing in Uji Japan—the home of exquisite matcha—and what structural issues would affect the growers’ responses.  It’s clear that the problems will be difficult to solve, but equally clear that we must solve them. (It was in the 70’s in Boston in January, only a few days earlier!)

Fitrio displayed a picture similar to this one, showing that tea growing in Uji occurs in the middle  of an urban environment, complicating the conditions for growing tea.
Photo by Arboramo, Wikipedia CC BY-SA 4.0.

• Of course, UC Davis is famed for its Viticulture & Enology Program, so we were guaranteed some super interesting information about wines. In particular, learned from Ron Runnebaum, Assistant Professor, Viticulture and Enology, UC Davis, about one of my favorite wines, Pinot Noir, and the effects of growing the wine in different places on the West Coast. Thoroughly nerded out on all the graphs and Principle Component Analyses—when I was at Cornell, had huge discussions with my graduate students about how to analyze our data—do you use Principle Component Analysis or Factor Analysis or neither? And how do you interpret the results?  Was thrilled to see some of my favorite tea scents mentioned on the graphs—scents that I used in my talk.

Day 2 was Sensory Day, introduced by Andrew L. Waterhouse, Director of the Robert Mondavi Institute of Wine and Food Science. Was especially glad to have met him—so very much appreciated his kindness as well as his knowledge.  

• Al Robbat, Director/Professor Chemistry Department Sensory and Science Center and Center for Field Analytical Studies & Technology at Tufts, and inventor of the most complex and effective systems for analyzing aroma chemicals ever, again brought home the effects of climate change on tea and tea quality. With his systems, you can clearly see what changes in monsoon patterns, for example, cause in tea chemistry. Have to look more deeply into this question for another blog post!

• So grateful to Sue Ebeler, Professor, Viticulture and Enology and Associate Dean, Undergraduate Academic Programs, College of Agricultural and Environmental Science at UC Davis, who provided a superb introduction for my experiential adventure that was to come later in the afternoon—she described many of the aromas I was planning to provide, and where they come from in wine and tea. 
• Nikolai Kuhnert, Professor Analytical Chemistry Jacobs University Bremen, Germany also had me nerding out with his talk about tannins entitled High Resolution Analysis of Black Tea and Wine. Nikolai was another of the kind thoughtful people I met at the conference—I can’t say it enough, the people at the Colloquium were people I am proud to be among.
• And Jonathan Cave, Treasury Wine Estates (https://www.tweglobal.com), who talked about tannins in wine, and reminded me of how anthocyanins alter the flavor profile of wines enough so that when added to white wine, people may become confused and think it might be red.
• Then it was my turn. I was fortunate to be able to give my talk at the Robert Mondavi Institute Sensory Theater, where people sat at desks in an amphitheater, with wines and teas arrayed in front of them. Rona Tison of Ito-En (https://itoen.com) provided three ready-to-drink teas, green, oolong, and black, and Mondavi provided a Chardonnay, a Pinot Noir, and a Cabernet. With the expert assistance of my friend Marzi Pecen (she is not only a tea specialist, but a parfumeuse) we handed out paddles/touches with scents on them, and had fun making the aromas of the teas and wines disappear and reappear. More about how this works in my next blogpost.
• Finally, after me came Andrew Waterhouse, with three Cabernet Sauvignons that were so different it boggled the mind. Three different ages, three completely different flavor profiles. Andy talked about what aging does to wine profiles, and neatly summed up what we had heard throughout the colloquium: sensory matters!

One more experience, so exquisite!  Susumu Yotsukawa, designer, www.kisendo.net, brought a collection of wine/sake and tea items to savor with our eyes. Here's one:

A sake cup designed by Susumu Yotsukawa, made of Japanese cherry birch and brass,​ available at https://www.woahjapan.com/product.asp?shocd=WJC00329

Go to the Kisendo website—www.kisendo.net—for more on which to feast your eyes!

==>> Available on Amazon in paperback, my latest book, "Tea: a Nerd's Eye View."