Tuesday, October 31, 2017

Pairing teas at TexSom

Friend of Pairteas Jason McDonald sent me several emails a while back about a tea-pairing tasting he, Jeni Doddand Kyle Stewart carried out at TexSom, the big Texas sommelier event.* I followed up with emails to both Jeni and Kyle to learn more about the teas and the experience.

Here's what Jason said about the ingredients for the pairings:
"We used an aged Gruyère and an aged white cheddar. We used a tea from my farm [The Great Mississippi Tea Company - http://www.greatmsteacompany.com] that is best categorized as a dark oolong or a lightly oxidized black tea. We also used a dark tea from Nepal that Jeni supplied."
Jason McDonald with the cheese!
The general consensus was that Jason's oolong paired better with the cheddar than with the Gruyère. as I noted to Jason:
"The cheddar has a number of compounds in common with oolongs...don't remember whether you were still there when we smelled indole at WTE [World Tea Expo]. It has an animalic smell that is characteristic of oolongs, and contributes to oolong's complexity. In addition, both cheddar and oolongs have a number of compounds that have an almond quality [including benzaldehyde], and dimethyl sulfide, which has a marine smell. All of these compounds activate the warm receptors. The result is that the tea and the cheese will enhance each other." 
I should add that the fattiness of the cheese would turn off the hot receptors (TRPV1), so the flavors of the compounds that activate the warm receptors would be enhanced. 

Meanwhile, Jeni Dodd gave me more detail about her Nepalese tea, which she had cold-brewed overnight. She wrote:
"As for the Nepalese tea I used.  It is a black oolong from the Ilam (more specifically Maipokhara) region in the Eastern part of Nepal.  There are two main tea growing regions Ilam and Dhankhuta.  The oxidation of this particular tea is about 55-65%."
This tea is called Wild Sunset tea. As Jeni noted, here's why:
"My friend, whom I consider one of the best tea makers in Nepal, discovered a tea garden that had been growing wild for almost 30 years.  This garden was at the epicenter of the 2015 7.8 devastating earthquake.
My friend decided to leave the successful tea garden he had been at in order to cultivate this garden in order to bring economic stability back to this devastated region.  I requested to him to keep some of the wild growth since you cannot replicate 30 years of wild growth easily.  This tea from the first harvest of the wild growth after 30 years.  It is processed as a dark tea and right now has about 1 year of age on it."
Here's how Jeni describes the tea:
"It is smooth and full-bodied.  I find hints of cherry, but a cooked cherry, a sweeter cherry.  But the sweetness is balanced by a maltiness.  There is little to no astringency and the finish lingers.  The finishing notes are a bit smoky, a bit tobaccoey.  When you inhale, you find the cooling sensation that has been informed by the Eucalpytus trees growing in the area.  But there isn't a minty flavor.  There is a brightness to the tea, I think it must be that cooling effect.  But it is so nicely balanced and grounded by the maltiness."
To me this description is rich in hints about the chemical composition of the tea! 

First about the cooling sensation that Jeni says comes from eucalyptus trees going nearby: the chemical that gives eucalyptus its aroma is 1,8-cineol, which does bind to both the cool (TRPM8) and the cold (TRPA1) receptors. That's why it gives eucalyptus that cooling sensation when inhaled. 1,8-cineol has an herbal quality, but not very much a minty one. This compound will give a brightness to the tea, but, as I noted in my most recent post, cool sensations don't last long and can be overtaken by sensations provided by activation of the warm and hot receptors. Activation of these receptors lasts in the mouth, hence the long smoky tobacco-ey finish.

As for the sweetness, that probably comes from benzaldehyde and methyl salicylate. Depending on context, benzaldehyde can seem almond-like or cherry-like. It's my impression that the flavor shifts more to cherry in the presence of compounds that activate the "warm" (TRPV3) and "hot" (TRPV1) receptors.

So what about maltiness? and the smoky tobacco-ey finish? I am going to ask Jeni about the wood or coal that was used for baking or roasting the tea and for how long. Depending on the method, you will get the formation of compounds such as 2-ethyl furan, which has a classic malty flavor. That's a compound in Indian teas that gives them a rich maltiness. It, and a host of smoky and tobacco-ey compounds, all activate "hot" receptors.

It turns out that the Nepalese tea went well with the aged Gruyère. Its lower fat content meant that it didn't interfere with the ability to taste the subtleties of the tea derived from activation of TRPV1. As Kyle said:
"Cold-brewing leaves behind the catechins (astringency) and accentuates the top notes (fruity, floral) of this amazing oolong.  Without the astringency, the cold brewed oolong did not pair as well with the high-fat cheeses. The British used milk to soften the astringency of English Breakfast tea." 
Furthermore, as Kyle noted:
"The black raisin and green apple notes of the tea blended beautifully with the earthy, nutty and bosc pear notes of the Gruyère."
One of the compounds that gives Gruyère its nutty flavor is 2,6-dimethyl pyrazine. This compound is known to be in black tea, and is formed when the tea leaves are heated up during processing. My guess is that—given the color of the tea and Jeni's mention of smokiness—this tea was sufficiently baked/roasted to create this compound along with the malt flavored compounds.

Jason has the last word for this post:
"The teas made the cheese more intense in both cases. It seemed that it was a good pairing side by side because one of the cheeses went flat and the other became bold with both teas. It was also interesting that they were opposite of each other. So, it was a happy coincidence."

* According to Kyle "TexSom (Texas Sommelier) is an annual wine education conference held at The Four Seasons Resort in Dallas.  The Cultured Cup, which also sells coffee, has been a sponsor of this conference since its inception 12 years ago." 

Thursday, October 26, 2017

Oolongs and fall fruits

Sara Shacket and her friends have been doing a series on tea pairings that is absolutely fascinating! The latest is about pairing oolongs with fruit, which you can find here:


That page has links to the tasting notes by Georgia (http://www.notesontea.com/2017/10/tea-pairing-101-oolong-tea.html) and Jee (https://www.ohhowcivilized.com), who shared in the experience, and had similar takes on the results. Be sure to read all three blogs about the pairings, because each reveals a different aspect of the experience.

The teas were a Taiwanese Bao Zhong, which is lightly oxidized (typically around 10%), a classic Chinese Tie Guan Yin, and an equally classic Xiao Hong Pao (Little Red Robe), which was the most oxidized of the three.

What oxidation does is to shift the tea's flavor profile from vegetal and "cool" to more chocolatey, sweet, and "warm."

The three fruits were pear, plum, and persimmon, chosen because they are all fall fruits. It so happens that these three fruits also fall on a spectrum from "cool" to "warm." 

Teas from left to right, Bao Zhong, Tie Guan Yin, and Xiao Hong Pao.
Image from  http://www.tea-happiness.com/2017/10/tea-pairing-101-oolong-and-fruit.html

Here are the overall results, compiled from the three bloggers: 

The pear went reasonably well with the Bao Zhong, as you would expect because both tend to activate the "cool" receptors, though the Bao Zhong, described as only somewhat vegetal, would be less effective with pear than, say, a green tea. 

The Tie Guan Yin was happiest with the persimmon. The persimmon was described as very sweet—it was one of the persimmon cultivars, Fuyu, that is not naturally astringent.* Sara  described the sweetness as "cloying." A major volatile flavor compound in persimmon is benzaldehyde, which has a characteristic sweet almond/cherry quality with nutty/woody nuances, and to my nose can indeed be very cloying. Bennzaldehyde activates the warm to hot receptors. Turns out that the more roasted an oolong is the less benzaldehyde it contains—so it is not surprising that Tie Guan Yin would go better with the persimmon than the more highly roasted Xiao Hong Pao.**

Plums went best with Xiao Hong Pao. Plum cultivars vary tremendously in their composition, but one constant is the presence of lactones such as gamma-decalactone and gamma-dodecalactone.*** These lactones have a waxy fruity quality and tend to activate the warm/hot receptors.**** Interestingly, plums also have several compounds such as linalool and hexanol that activate the cool receptors. Sara, though not the others, noted that the plums went well with the lightly oxidized Bao Zhong: in contrast with the pear, "The plum turned out to be a better choice. Its sweetness worked well with the floral and savory notes, but didn't overpower the palate. The tart plum skin transformed the tea flavor, creating an interesting depth." My guess is that the depth came from the back and forth across the cool to warm receptors that each activated.

Which brings me to what I thought was the most fascinating observation with these pairings, about the pear and the Xiao Hong Pao, as described by Sara: 

"We had a strange experience with the pear- it seemed to erase the flavor of the tea, but then a moment later the tea lingered on the palate. Jee decided that the pear was similar to a palate cleanser, which was an interesting thought!"

It was indeed an interesting thought! What palate cleansers, such as the cool sorbet of classical French banquets, do is to reset the balance of the trigeminal system. Here's how this works:

The response of trigeminal receptors at the "hotter" end of the spectrum is slow-on slow-off, while the response of those at the "cooler" end is quick-on quick-off. Think about eating a chili-laced food. At first you may not think it's too spicy, but then the heat sneaks up on you—that's the slow-on. You reach for some ice water, which quickly cools down the burn—that's the quick-on. But wait a few seconds and the cool receptors turn off and the heat returns! Signals from the "hot" receptors were just suppressed, but because they are slow-off, they were still active when the "cool" receptors had stopped sending signals to your brain. Remember that the sequence here is important.

This is exactly what was happening with the pear and the Xiao Hong Pao. This highly oxidized tea is full of chemicals that activate receptors at the hotter end of the trigeminal spectrum, while the pear activates receptors at the cooler end. Sip the tea, and the hotter end is activated. Bite into the pear, and the tea disappears. Wait a little, the pear flavor vanishes and the tea effect (which has been there all along) returns.

I've not mentioned here that all three bloggers found that honeycomb went well with all the teas, and managed to cover up what I would call the disagreements among the tea and fruit flavors. That will be a discussion for another blogpost.

And to find out more about the trigeminal system and what it means for tea and tea pairing, find my book "Three Basic Teas & How to Enjoy Them" at Amazon!

* Lyon, B. G., Senter, S.D. and Payne, J.A. (1992), Quality Characteristics of Oriental Persimmons (Diospyros kaki L. cv. Fuyu) Grown in the Southeastern United States. Journal of Food Science, 57: 693–695. doi:10.1111/j.1365-2621.1992.tb08074.x

** For the chemical profiles of panned and unpanned oolongs, go to: Sheibani E, Duncan SE, Kuhn DD, Dietrich AM, Newkirk JJ, O’Keefe SF. Changes in flavor volatile composition of oolong tea after panning during tea processing. Food Science & Nutrition. 2016;4(3):456-468. doi:10.1002/fsn3.307. You can find the article online at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4867765/.

*** Y. H. Hui, Feng Chen, Leo M. L. Nollet. Handbook of Fruit and Vegetable Flavors. John Wiley and Sons, 2010. Also, go to http://www.flavours.asia/uploads/7/9/8/9/7989988/flavor_of_plums.pdf

**** Incidentally osmanthus, which goes so well with Tie Guan Yin, also has these lactones.