Oolong-hai and lychees

Came across this fascinating photo by Chinh Le Duc when searching for tea images on Unsplash.com. The title words read: "Drink, glass, cocktail, beverage and alcohol."  

Photo by China Le Duc, Unsplash.com

Alcohol? When my keyword search was "tea?" What is going on here? 

Come to find out that there is an iced alcoholic beverage called oolong-hai consisting of oolong tea combined with shōchū, a Japanese drink fermented and distilled from any one of a number of starches, including rice, barley, buckwheat, and interestingly, sweet potatoes. Apparently the choice of starch conveys a distinctive flavor to its shōchū. 

Here's what Sara Shacket of the blog Tea Happiness* has to say about the oolong-hai she savored:

"The drink was incredibly refreshing on a hot NYC summer evening. I tasted the slightly bitter earthiness of the Oolong, along with a subtle hint of something smoky that reminded me of whiskey. Shochu has a subtle flavor, and so my drink didn't have the overwhelming alcoholic taste that I usually expect from a cocktail. This makes the drink quite dangerous for me. I hardly even noticed that I was consuming any alcohol! It had a similar refreshing feel to the mugicha I recently tried.  I also love that it wasn't sweet. In fact, the server warned me that it wasn't a 'sweet cocktail'."

At another (commercial) website,** found a good photo of oolong-hai, along with a recipe:

Oolong-hai from https://umamimart.com/blogs/main/japanify-oolong-hai

Comparing this photo with the one by Chinh Le Duc, it looks very much the same: same color and cloudiness. 

Which led me to the next question, namely would lychees go well in this drink?

Looked up the chemistry of lychees in a paper by colleagues of mine from Cornell, Peter Ong and Terry Acree.*** Turns out that lychees share a number of flavor-significant compounds with oolongs. Some of these, such as linalool, are found in all teas, but the one that stood out for oolongs specifically is furaneol, aka strawberry ketone, which activates the warm receptor, TRPV3. Another important flavor compound in lychees, and perhaps in some oolongs, is vanillin, which also activates TRPV3.  But most striking is the presence in oolongs of cis-rose oxide, which has a characteristic lychee aroma.**** Put together, oolong and lychee will each expand the flavor of the other.

In case you are wondering, I haven't experienced the drink myself. I lack functional aldehyde dehydrogenase, so become quite sick with very little alcohol, and despite my love for oolongs, I really don't like lychees—and now I know why. Lychees have δ-decalactone, which has a strong flavor of coconut. Can't stand the flavor of coconut, and lychees come across as too coconutty to me. So I am not about to try this drink, no matter how hot it gets this summer. 

But you might enjoy it very much!

* http://www.tea-happiness.com/2011/08/oolong-shochu-yes-please.html
** https://umamimart.com/blogs/main/japanify-oolong-hai
*** Ong, P.K.C., and Acree, T.E.. Similarities in the Aroma Chemistry of Gewürztraminer Variety Wines and Lychee (Litchi chinesis Sonn.) Fruit. J. Agric. Food Chem., 1999, 47 (2), pp 665–670
DOI: 10.1021/jf980452j.
**** Sheibani, E., Duncan, S. E., Kuhn, D. D., Dietrich, A. M. and O'Keefe, S. F. (2016), SDE and SPME Analysis of Flavor Compounds in Jin Xuan Oolong Tea. Journal of Food Science, 81: C348–C358. doi:10.1111/1750-3841.13203