The Tearoom - Part 1 - What the brain does with a story: Charles Rennie Mackintosh Willow Tearoom

In contemporary marketing the mantra is “You are selling a story…not a product.”  

This mantra led me to read a recent article in the New York Times,* which interpreted a paper in Nature,** as saying what happens in the brain when you listen to a story. According to the NYT, the words in the story elicit neural connections that gather information from all parts of the brain, so that you become immersed in the experience as if it were real, and you no longer experience the reality of the outside world. 

So when I heard the word “Tearoom” today I first thought of the perfectly designed and curated Gypsy’s Tearoom, located in a 1760 house in Westminster Maryland, surrounded by green grasses, where I recently enjoyed a classic “afternoon tea” served in the classic manner, with classic teas and classic tea sandwiches and more (will go into these in another post)…

Gypsy's Tearoom, Westminster, Maryland

…when my thoughts leapt to a tearoom in Glasgow. Several years ago, my daughter and I made the pilgrimage to the Charles Rennie Mackintosh Willow Tearoom, as much for its design as for its tea.

The Room de Luxe at Willow Tearoom, Glasgow, Scotland.***

We sat at the table to the far right in this image, where you see someone serving tea. From this vantage point we could survey the whole room, though we couldn’t get a glimpse of the busy noisy grey street below. 

This is the “Room de Luxe,” as it was called when first created: white white white, with the soft purple upholstery and the shocking pink glass squares in the chairs. White for cleanliness, health, and purity, purple for a hint of royalty, and pink, because tearooms were, in contrast to coffee houses, women’s places—a color between playful innocence and discrete sensuality. 

If we had sat at one of the tables shown in the image below, we could have included the street in our purview. And we could have seen people rushing by, very few entering the building where we sat.

Another view of the The Room de Luxe at Willow Tearoom, Glasgow, Scotland.***

The place was sad to us—the spirit of excitement and novelty was gone, of course—art nouveau is hardly nouveau anymore—but at the same time the fixtures themselves don’t age well despite restoration in 1983. As Wikipedia says: “The tea room however has fallen into disrepair and is now lacking its originally intended atmosphere and quality. Fans of Mackintosh are urgently calling for a more sympathetic restoration.”

What a contrast to the 1760 building that houses Gypsy’s Tearoom: it has aged gracefully, and in fact a little aging coupled with a little nostalgia made it all the more attractive!

Gypsy's Tearoom, Westminster, Maryland.

* http://www.nytimes.com/2016/04/29/science/this-is-your-brain-on-podcasts.html?action=click&contentCollection=science&module=NextInCollection&region=Footer&pgtype=article&version=column&rref=collection%2Fcolumn%2Ftrilobites

** http://www.nature.com/nature/journal/v532/n7600/full/nature17637.html

*** Photos of The Room de Luxe at The Willow Tearooms, Glasgow designed by Charles Rennie Mackintosh in collaboration with Margaret MacDonald for Catherine Cranston. Photograph taken on 9 March 2006 by User:Dave souza. 

Receptor rivalry: an experiment.

Recently gave a talk about pairing tea with foods/herbs/spices to a lively group of tearoom people. Started out with my favorite receptor experiment, one that you can do at home:

Mint and Cinnamon. Photo courtesy tea connoisseur Marzi Pecen — thanks Marzi! 

Take a mild cinnamon candy and a mild peppermint (I use Brach’s® cinnamon hard candy and Lifesaver® peppermint candy). First put the cinnamon candy in your mouth, get a good cinnamon flavor going, then take the candy out. Next put the peppermint candy in your mouth: the cinnamon flavor instantly disappears. Then wait—after a short while the mint flavor disappears, and gradually the cinnamon comes back, faintly but perceptible for most people.

What is happening? The cinnamon slowly binds to the hot receptor TRPV1, where it stays. When you put the mint in your mouth, the menthol activates the cool/cold receptors (TRPM8 and TRPA1). Activation of these receptors turns off TRPV1, so you no longer taste the cinnamon. The amount of time that menthol stays on these receptors is short (= short residence time), so the menthol flavor disappears. Meanwhile, the cinnamon sits on its receptor for a longer time, and is still there when you take out the mint. Therefore, once the mint flavor is gone, the cinnamon receptor is no longer inhibited, so you can now taste the cinnamon again.

This is a good demonstration of what can happen when you eat a meal, with items that activate one or another receptor. Once you call your attention to this kind of progression, you will experience it again and again.

More about the talk I gave in the next post.

Why is white tea flavor so elusive?

Been thinking a lot about white tea, with its elusive flavor. Specifically, have been fascinated by the compositional differences between white tea and green tea: in fact there are few differences, yet white tea’s aroma is so much more elusive than that of green tea. Why?

To my delight, found a paper that includes white tea in its analyses (most only consider green, oolong, and black).* I thought I may have found the answer…

According to the data in this paper, the difference doesn’t seem to lie in the usual “green” compounds, such as hexanal, with its flavor of cut grass (yes, cut grass emits this chemical), nor in the citrusy flowery compounds such as E-geraniol and linalool, which help give both green and white tea their rose-like and citrus-like aromas. Rather, it seems that the critical difference lies in the presence of nerolidol in green teas and its relative absence in white teas.

Nerolidol has a green, citrus flavor, but most importantly it provides much of the woody flavor that we expect in tea. In perfumery, it is considered a base note that serves as a fixative for other aromas, while providing a subtle addition for blending flower and citrus top notes.** In other words, it is an aroma that has staying power, and may, if the data in this paper are correct, give green teas the flavor “heft” that is missing from white teas. One can almost think of it as a dial that increases the “volume” of the other green ingredients in the tea. 

So I looked further into nerolidol, and found a paper on the nerolidol content of teas, including white tea.*** In this analysis, white tea and green tea have virtually the same amount of nerolidol…so what to think now?

Neroli flower, from the bitter orange tree

(Citrus aurantium subsp. amara or Bigaradia —you can see the green fruit in the upper right corner). 

Nerolidol is one of the characteristic compounds in neroli flower oils. Image from moreguefile.com.

_______

* Kunbo Wang, Fang Liu, Zhonghua Liu, Jianan Huang, Zhongxi Xu, Yinhua Li, Jinhua Chen, Yushun Gong, Xinghe Yang. Comparison of catechins and volatile compounds among different types of tea using high performance liquid chromatograph and gas chromatograph mass spectrometer: Catechins and volatile compounds. International Journal of Food Science & Technology, ISSN 0950-5423, 07/2011, Volume 46, Issue 7, pp. 1406 - 1412.

**https://www.perfumersworld.com/product/nerolidol-3LM00319; http://www.aftelier.com/Nerolidol-p/bot-nsio-nerolidol.htm

*** Chunhua Ma, Yanqin Qu, Yingxue Zhang, Bin Qiu, Yiru Wang, Xi Chen. Determination of nerolidol in teas using headspace solid phase microextraction–gas chromatography. Food Chemistry. Volume 152, 1 June 2014, Pages 285–290.

Some thoughts about cocktail drinking, whether tea-containing or not...

I’ve been often asked about how to create cocktails using tea, and what flavors of tea, spirits, and additions to use. I’m hesitant to answer this question, because I can’t make the experiment myself to see whether flavor reality matches theory. 

That's because I don't drink alcohol, because genetically I lack the enzyme to metabolize it,—even a little bit of alcohol makes me very ill.  Thus I can’t tell from personal experience what cocktails are like, and what would work well. Furthermore, in addition to being intolerant of alcohol for metabolic reasons, I am genetically programmed to be hypersensitive to the burn of alcohol…so all in all, I’m a tea-totaler!

That said, I did analyze some data about consumer cocktail and wine drinking for Tim Hanni, Master of Wine. 

People in the US were invited to fill out an on-line survey between December 2009 and March 2010. Out of 1485 usable responses, 324 preferred sweet wines, so we called them “Sweet” and 341 were tolerant of high alcohol dry wines such as Cabernet Sauvignon, so we called these people “Tolerant.”

From other data, we know that people in the “Sweet” group are more sensitive to the burn of alcohol, and also more sensitive to the bitterness of coffee. In fact, overall they tend to prefer tea to coffee, and if they drink coffee, 64% say they put some flavoring and/or creamer/milk in it, either always or sometimes.

By contrast, people in the Tolerant group, are generally less sensitive to the burn of alcohol can tolerate high alcohol dry wines, and are not put off by the bitterness of coffee. They prefer coffee to tea, and 67% of them drink their coffee black, with no additions.

When we looked at cocktail versus wine consumption, the difference between the two groups was striking. Here’s how they answer the question: “When you are at a bar or non-dining social function/party, what is your primary choice for an adult beverage?” The numbers are the percentages of respondents.

These differences are statistically significant for wine and cocktail drinking, with more than half of the Tolerant group opting for wine, and fewer than a quarter opting for cocktails. Slightly more than a third of the Sweet group chose either wine or cocktails. Considering that this survey was geared towards wine, this proportion of cocktail drinkers among the Sweet group may be an underestimation of the actual proportion among people who are highly sensitive to alcohol’s burn, and tend to prefer tea to coffee. 

To my thinking, these data help me understand why I’ve had so many requests for help with developing tea-containing cocktails!

You can find a summary of the study at: http://www.timhanni.com/ConsumerStudySummary.pdf.

Should we enhance the flavor of black tea by treating the plants with an injury compound?

Plants that are injured release volatile compounds that not only help to protect the plant but also “warn” surrounding plants which then produce defense compounds themselves. In previous posts we have discussed the effects of thrips and jassids in enhancing the aromas of second flush Darjeeling and Oriental Beauty Bai Hao teas respectively. Apparently you can have some of the same effects without the intervention of insects, simply by spraying the tea with one of the plant’s defensive volatile compounds, methyl jasmonate.

Shi and colleagues sprayed tea plants with methyl jasmonate in an alcohol solution 24 hours before plucking the bud and two leaves to create the tea. Control plants were sprayed with water. (One wonders what the alcohol might have contributed…though it probably evaporated quickly).*

The gene expression for two enzymes important for black tea aroma increased in the treated tea: β-primeverosidase and polyphenol oxidase. β-primeverosidase releases linalool, linalool oxides, and geraniol from the sugars to which they are bound, thus releasing their aroma. Polyphenol oxidase is important for the formation of theaflavins and thearubigens. Thus an increase in these enzymes may be expected to increase the quality of a black tea.

Indeed, methyl jasmonate noticeably altered the profile of aromatics in the resulting teas, with an increase in linalool and its oxides, which have a characteristic floral aroma, and a decrease in 3-hexen-1-ol, which has a rather bitter “green” smell. Other “green” cool/cold receptor activating chemicals decreased as well, with the result that a panel of tasters found the tea from treated leaves to be more honeyed, sweeter, and more floral. By decreasing the number of compounds that activate the cool/cold receptors, there is less inhibition of the warm/hot receptors, so the black-tea qualities of the tea stood out.

The fact is that we treat tea leaves at and after plucking in order to activate the injury responses in order to yield a more aromatic tea. The question is: should we be nudging the process by “fooling” the leaves into response-to-injury mode before they are even plucked?

Image below: a thrip (tiny brown strip-like object) on a petal of the tea Camellia in Darjeeling—natural aroma creation through insect injury. From a fascinating article about autumn harvest Darjeeling at Hojo Tea: http://hojotea.com/item_e/b06e.htm

* Jiang SHI, Li WANG, Cheng-ying MA, Hai-peng LU, Zong-mao CHEN, Zhi LIN.  Aroma changes of black tea prepared from methyl jasmonate treated tea plants. J Zhejiang Univ-Sci B (Biomed & Biotechnol) 2014 15(4):313-321.

A graphic demonstration of the differences among green, oolong, and black teas.

Here’s a graph from the paper by Li-Fei Wang and colleagues that I mentioned in yesterday’s post.* It characterizes the aroma chemicals in tea through solid-phase microextraction–gas chromatograph (SPME–GC).  The top graph comes from a green tea (Ouksu tama-ryokucha, which is both steamed and roasted), the middle graph from a Dong-Ding (Tung-Ting) oolong, and the bottom graph from an English breakfast  (black) tea. The height of the peaks indicates the abundance of each chemical in the extract.

SPME–GC separates the chemicals that have a “green” quality—in other words chemicals that activate the cool/cold receptors—from the chemicals that activate the warm and hot receptors. I drew the green line to show the border between the two types of chemicals, primarily cool/cold on the left, and primarily warm/hot on the right.

As you can see, the green tea’s aroma chemicals (top graph) lie predominantly to the left of the line, which corresponds with the fact that green tea pairs well with foods that have a cool/cold aroma such as lemon, mint, and ginger.

As you go to the next graph, from Dong-Ding oolong, you’ll notice a marked difference from the green tea graph, with high peaks to the right as well as to the left. Note too, that there are far more high peaks altogether, consistent with the complexity of oolong flavor. Oolongs can be paired with both cool/cold and warm/hot aroma foods, though pairing is best with foods such as rosemary and strawberries that activate the primarily the warm (not hot) receptors. 

Black teas have very little of the green chemicals, and a somewhat lower quantity of the warm/hot aromas than oolong (bottom graph). The net effect is a far less complex flavor than that of the oolong, but the lack of cool/cold aromas means better pairing with foods with aromas that bind to hot receptors, such as raspberries and chocolate.

* Li-Fei Wang, Joo-Yeon Lee, Jin-Oh Chung, Joo-Hyun Baik, Sung So, Seung-Kook Park. Discrimination of teas with different degrees of fermentation by SPME–GC analysis of the characteristic volatile flavour compounds. Food Chemistry. Volume 109, Issue 1, 1 July 2008, pages 196–206.

Jasmine tea, fake and real…

Have been exploring a fine paper in the journal Food Chemistry by Li-Fei Wang and colleagues that characterizes the aroma chemicals in tea through solid-phase microextraction–gas chromatograph (SPME–GC).*

True high quality jasmine tea is made through a laborious process in which jasmine flowers come into contact with green tea multiple times. Each time, the used flowers are removed, the tea is allowed to dry down, and fresh flowers are added back. In the process the tea/flower pile can reach temperatures as high as 40-48º C, as chemicals in the flowers and tea together undergo metabolic transformations and exchange of volatiles.

A major transformation is the loss of the typical green tea compounds that impart a grassy green flavor. These include 2-methyl butanal, 1-penten-3-ol, and 2-penten-1-ol, and especially n-hexanal. The only major “green” compound left is cis-3-hexenol, which has a fresh, fruity green aroma. At the same time the amount of volatiles that bind to warm and hot receptors increases. Two compounds that smell of jasmine, linalool and benzyl acetate, are relatively increased as well. Further, compounds such as methyl jasmonate are formed in response to stress, which add to the flowery aroma. At the same time, the treatment increases oxidation of the tea so that the result is a tea that resembles an oolong or even a black tea.

Fake jasmine tea is spiked with jasmine chemicals in order to give a jasmine odor. It may smell of jasmine but the jasmine flavor is faint or absent in the brewed tea.

The reason is that “green” chemicals remain in fake jasmine tea after treatment, because no metabolism occurs. These chemicals turn on the cool/cold receptors and turn off the warm receptors to which most jasmine-related compounds, with the exception of linalool, bind. At the same time, these jasmine compounds try to turn off the cool/cold receptors. The net effect is a tea that smells of jasmine but tastes like a weak green tea. 

Here are chromatograms from this paper that show the differences among green, true jasmine, and fake jasmine teas. The peak just to the right of the green line is cis-3-hexenol.

• The top chromatogram is from green tea. The peaks to the left of the green line correspond chiefly to the “green” compounds in the tea, which bind to cool/cold receptors.
• The middle chromatogram shows the peaks in true jasmine tea. The peaks to the left of the green line are tiny, while the peaks to the right are much higher. These peaks correspond to jasmine aromas and flavors, and to the tea compounds from leaves with a higher degree of oxidation, akin to oolong or even black teas.
• The bottom chromatogram corresponds to a fake jasmine tea. Many green tea peaks remain, and the peaks to the right of the chromatogram are much diminished in size relative to the ones in the true jasmine tea.

…that’s why the receptors in your mouth will know it when they meet a fake jasmine tea, even when your nose may be fooled!

* Li-Fei Wang, Joo-Yeon Lee, Jin-Oh Chung, Joo-Hyun Baik, Sung So, Seung-Kook Park. Discrimination of teas with different degrees of fermentation by SPME–GC analysis of the characteristic volatile flavour compounds. Food Chemistry. Volume 109, Issue 1, 1 July 2008, pages 196–206.