"Mocha" has worked its way into my vocabulary as a wine descriptor over the past decade or so. I use it in reference to the aroma of a caffè mocha, particularly that dusting of cocoa powder on top of the foamed milk.
I first used "mocha" as a tasting descriptor in the magazine in 1998. In 2000, it appeared in 43 Cailfornia wine reviews and 150 Wine Spectator reviews from around the world; in 2005, it appeared in 134 and 246, respectively. So far this year, "mocha" has popped up in 232 reviews of California wines (out of more than 3,700 total), and it's been used in 614 reviews of nearly 20,000 wines around the world, so it's not just me: Mocha's popularity as a tasting descriptor is at an all-time high.
So is mocha's prevalence as a wine descriptor simply a product of caffè mocha's popularity as a beverage, and the proliferation of coffee culture in general? Or is there something different about the wines of today that evokes that aromatic blend of chocolate and coffee?
I've been curious as to where that mocha aroma in some wines originates.
The most obvious (at least to me) source of mocha in wine is oak. Oak can give wine all kinds of flavors and aromas—vanilla, smoke, cedar, various nuts and tree scents. Those and many others are identified on Ann Noble's Wine Aroma Wheel, which provides a visual graphic of the different categories and aroma components that one can encounter in wine. I have one in the office and one at home, and so should you. If you're new to wine, it's a valuable resource.
Science backs up the assertion that mocha aromas can be a product of oak aging. According to François Chartier's Taste Buds and Molecules, the aroma of chocolate comes from aldehyde derivative organic compounds such as acetylpyrrole, which is generated when oak barrels are toasted. That and other compounds generated by heating oak, such as furfurals (coffee and roasted almond aromas), isomaltol (burnt sugar and caramel) and eugenol (nutmeg), can all be absorbed by wine aging in toasted oak barrels, and would account for all those mocha descriptors.
But is that all it is? In my travels to wineries and visits with winemakers in the past few months, I've asked vintners if they identify "mocha" in their wines and, if they do, where they thought it originated?
They all offered that it could come from oak. But many also said they could smell mocha as the grapes were being crushed, as well as during fermentation, well before the wine goes into oak barrels. It surprised me on one hand, but also makes sense: Chocolate and coffee both start out as fruits, just like wine.
Wines aged in toasted oak barrels are certainly likely to show off those mocha aromas. I suspect that mocha shows up more often in wines made from riper grapes as well. Both could be reasons that mocha seems more evident in wines today than wines from the past, which were picked at lower ripeness levels and were much less frequently aged in new toasted oak.
What's been your experience with mocha as a wine descriptor? Do you use it? And if so, do you find yourself using it more often these days?