My doubts about Yixing

[brunogm]

First, please note that I will be talking about Yixing teapots in terms of improving tea taste. This is not about Yixing teapots as art pieces and collector items.

I am a tea newbie, and I am trying to learn. Part of learning involves checking if Yixing teapots are superior vessels for brewing tea.

I bought a few Yixing pots, in different clays and at different price levels. Then I tested various permutations of teas and pots. I found it true that some unglazed clays alter the taste of tea, often in a good way.
Actually, I am now dedicating a Yixing teapot to Bai Ji Guan (which I found tastes completely unlike other yancha).

I wrote some unglazed clays alter taste and not Yixing on purpose. Because I have doubts about Yixing being unique. Why should it be unique? There are many million tons of clay on earth and many thousand quarries.

A lot of the terminology explaining Yixing quality (porosity, thermal conductivity) is exactly the same as the one used in refractory science. I have some contacts in the refractory business (eg http://www.refra.com/). Talking to them, I have no doubt that if there was money in it, a company would be able to create "synthetic" clays with similar kiln outcome as "natural" Yixing (in terms of porosity, thermal conductivity, iron content...).

So here was my first doubt. My second doubt is due to the fact that I could not find any serious academic studies about the impact of Yixing on taste. Where are the controlled experiments (same water, same pot shape and thickness, same temperature, randomized tasting order)? Where are the blind tests? Where are the control groups? Where are the statistical analyses?
Without those, there is no way you can tell for sure that Yixing is superior. In particular, there is no way to factor out placebo effects.

This situation reminds me a lot of wine. I am a tea newbie, but I am French, which means I know a bit about wine (including some elective classes in oenology and wine tasting). Blind tests can be pretty sobering for so-called wine experts. Most people can't even tell the difference between white and red wine when they taste it blind (tea is different, it is easy to recognize, but I am not talking about tea here, I am talking about the effect of Yixing).
A lot of wine rankings are just plainly wrong (like the 1855 Bordeaux wine classification). Those French wine rankings are just hype, marketing tools.

Hype brings me to my third doubt. Two Chinese persons taught me something about Chinese marketing.
First one is a local tea shop owner I buy tea from. She knows tea well, because when I tell her about a tea I like, she is able to find a similar tea I will like too, albeit from a different region.
She is selling Yixing pots but she actually discouraged me from buying any from her, saying she does not understand why people buy her pots, unless it is for decoration. According to her:
- there are many crappy pots in which never to brew tea.
- pots with good clay will indeed brew good tea when well-paired.
- but past a certain level of quality, it is stupid to overpay, because no one can actually tell the difference (just like expensive wines!), and opinion will vary from person to person.
- exact Yixing clay quality is hype, most clays are mixed.
- clay pots are not the best choice for some teas (e.g. Gao Shan Cha)
Her conclusion was: a lot of marketing.

Second Chinese person is a Chinese trainee at work. I was talking about Wuyi yancha from Fujian. She is from Jiangxi. She told me the Wuyi mountain range extends to Jiangxi, which produces tea just as good as Fujian tea. The difference is that the Fujian guys are great marketers whereas in Jiangxi they are not. Maybe she was only being patriotic about her province. But then I asked about Yixing clay and she said the same thing: cute pots and lots of marketing (I should know, my Chinese grand-father was a serial entrepreneur).

We are at the end of this long message. To summarize my three doubts about Yixing being a uniquely superior clay type for brewing tea:
- I am pretty sure similar clays can be found in nature or manufactured
- Where are the scientific studies?
- Some people can be pretty good salesmen

[Poohblah]

So here was my first doubt. My second doubt is due to the fact that I could not find any serious academic studies about the impact of Yixing on taste. Where are the controlled experiments (same water, same pot shape and thickness, same temperature, randomized tasting order)? Where are the blind tests? Where are the control groups? Where are the statistical analyses?
Without those, there is no way you can tell for sure that Yixing is superior. In particular, there is no way to factor out placebo effects.

You're throwing around a lot of talk for somebody with just one post to their name!

Why would any academic have an interest in conducting this study? Surely it's not academics who are interested in Yixing, other than for things like history and archaeology and anthropology. It's tea drinkers who are interested in Yixing pots, and indeed it's tea drinkers who appreciate the different experience that Yixing pots bring when used to brew Chinese teas. Secondly, we recognize that Yixing pots are not unique - Taiwanese and Chao Zhou pots are good choices for brewing oolong and pu'er as well. Furthermore, there are other reasons that a tea drinker would appreciate a nice pot besides its affect on taste. For instance, the pot is a nice addition to the tea experience, bringing the tea drinker more joy. And the artistry of the pot is something to appreciate as well.

In conclusion - though the market for Yixing may be driven by marketing, as you have pointed out, we tea drinkers have many reasons to seek out Yixing pots. For evidence, look at all the threads on Yixing pots in this forum. Look at the posts outlining how to pair pot with a tea. And I can tell you from personal experience (though I own no Yixing pots myself) that tea simply tastes better when brewed in a good pot. There's a body of knowledge out there about the different effects of different clays and so forth - there's a reason it exists.

[the_economist]

Skepticism is great. Trust your tongue.

[brunogm]

Why would any academic have an interest in conducting this study?

This would make for a nice PhD thesis. I have seen more futile ones.

For instance, the pot is a nice addition to the tea experience, bringing the tea drinker more joy. And the artistry of the pot is something to appreciate as well...

This I do not deny. Just to be clearer:

- I am not talking about art and collectibles here, just about tea taste improvement.
- I have read many threads, been lurking for a few months.
- I am already into this stuff, as I wrote, I am dedicating a Yixing teapot to Bai Ji Guan. I can appreciate how a nice teapot adds to the drinking experience. I love how this teapot is gaining patina at an incredible speed.

Tea is good in this teapot. But... But... It is just that I am not sure it is better than in a gaiwan. It is different, for sure. But depending on my mood, or on tasting order, or on the steep number (eg 1st steep vs 6th steep), I can find it either better in the gaiwan or in the Yixing pot.

This is worst than placebo. If it was placebo, I would probably find it always better in Yixing. Here I would say, the factors that count are, in this order:

tea quality + water quality + brewing parameters (temperature, time) > mood > pot

Pot impact comes only third.

... I believe in the scientific method, not in post-modern mumbo-jumbo.
And I daresay I know something about mumbo-jumbo in food/drink from my experiences with wine.

So I am just trying have a discussion on this subject.

[TIM]

Welcome to teachat. Please tell us more about your tea pot and Yancha. Where are they from and pictures if possible?

[Drax]

Welcome, bruno!

I share your frustration with the lack of scientific information.

I think academics would be interested in this topic -- from food scientists to material scientists. If you have the ability to understand how a material can enhance good qualities of teas, then you have a way to replicate it and (of course!) try to enhance it even more.

You do see the occasional scientific paper and study on wine, and as you mention, they are often quite sobering.

The scientific papers we usually see about tea are about chemical composition, and not much else (and often from institutions in China -- not that there's anything wrong with that; not surprisingly, most of the interest comes from China).

Tea tastings generally involve comparing different types of teas (not blind tasting) and so always come down to individual preferences. Very rarely do comparisons involve different brewing methods (other than the ones many of us conduct informally in our own homes) -- although we've had discussions about water types and other effects here in the past.

So if you restrict your interest only to how the clay alters the taste, then yes, it is likely that the "yixing clay" is not unique. But, Yixing pots do bring a lot of other things that you mention (artistry, history, and yes, marketing), which are difficult to separate, and makes them what they are -- very different from Japanese kyuusus or British high tea pots...

Each of us weigh a very wide array of variables when we determine the value of something like a yixing pot, and some of us will value certain aspects more than others (regardless of marketing... or so I'd like to think ).

[brunogm]

Welcome to teachat. Please tell us more about your tea pot and Yancha. Where are they from and pictures if possible?

Well, the gist of my original post was using the scientific method to assess Yixing clay superiority in brewing tea, while being wary of ballyhoo. It was not to discuss teas or show teapots.

I do not have a camera except the ones from my phone and tablet. They are very poor quality, but if I can fix that, I'll post my teapots in the "show off your teapot" thread.

Nevertheless and in the meantime, I will try to answer your question without pictures, even though I am feeling it is beyond the subject of this specific thread.

- My Bai Ji Guan: some from "Dragon Tea House", some from "Maison des trois thés", a local tea shop in Paris.

- The Yixing pot paired with Bai Ji Guan is a cheap pot from Dragon Tea House, which they described as:
The material of it has been stored in Yixing Zisha No. 1 Factory (former state-owned) since 80s . The mud is called as Lao Pin Zi (aged blended purple clay), which was dredged from shaft #4. Lao Pin Zi is a special clay for Yixing Zisha No. 1 Factory.

In my tasting spreadsheet, I wrote down that it was not necessarily better than a gaiwan. But I really like the speed at which this teapot is gaining patina. In terms of taste, it is acting like a prism diffracting light. I do not know how else to describe its effect on taste. Compared to the gaiwan, it is diffracting taste. Something like making it less intense while spreading it around the spectrum. Different, not necessarily better, but very interesting.

Before you tell me that I do not have a clue or experience about Yixing based on one cheaper pot bought on the internet, I should mention that I have other pots, and they tend to provide the same experience and foster the same doubts.
For instance, I have a Taiwan-made pot, Zhuni style, very thin, very high fired, similar to the couple ones that are drawing praise in the "show off teapots" thread. Made in Taiwan by Taiwanese people, for Gao Shan Cha. I have dedicated it to light fired Tie Guan Yin. It improves my light fired Tie Guan Yin. But I am not using it for the Gao Shan Cha it was supposedly made for. My Gao Shan Cha is much better in a gaiwan or surprisedly in a cheap thick walled pot I bought from Yunnan Sourcing.

This Gao Shan Cha that works well for me in the thick walled cheap Yixing pot from Yunnan Sourcing, is aged Alishan or Da Yu Ling from 2002 and 2008. So it is not green stuff. Maybe the really green stuff would be good in the Taiwan-made pot. I have not tried this because this pot is now committed to Tie Guan Yin.

This is complicated.

[bagua7]

Don't forget that China is an ancient culture (10,000 to 4,000 B.C. → Painted Pottery) with deep roots in Taoism whereas France is not.

Start to examine and explore Taoism/Daoism and you'll approach Yixing pottery from a different perspective. Lab tests can't examine the level of consciousness that Qi brings about in Yixing pots.

[battra]

I do also have my doubts regarding some claims regarding yixing pottery - much of what I have seen written about it seem to be a belief in their magic power rather than a scientific theory - for example some very complicated methods for seasoning them.
I am sure yixing pots and similar pots can brew very good tea - I have had good tea from such pots even though I do not own one.
But if a yixing pot should add to the flavour of a tea, or change the flavour, from a scientific point of view, that would mean that either
* the pot should absorb melecules from the tea
* melecules from the clay is released into the tea
* molecules from old tea drinking sessions dries into the pot, and is subsequently released into the tea (perhaps after some chemical process that transforms tham into different molecules?)

It would be interesting to see this clarified. Personally, I think that the only properties of a pot that impacts the tea is the thermodynamical properties, and whether it is beautiful.

Anyway, I did find an article:
An analysis of the chemical composition, performance and structure of China Yixing Zisha pottery from 1573 A.D. to 1911 A.D.
To read the complete article, you would have to access it from some university or library with access to the Ceramics International Journal.
At least there seem to be some research into yixing clay at Jingdezhen Ceramic Institute and Shanghai Institute of Ceramics. Perhaps more is published in Chinese?

[Drax]

battra -- you missed one function the pot could be performing (and perhaps others, I have not thought about this too hard): the pot catalyzes the decomposition or combination of molecules.

When pots can have heavy metals such as iron (or manganese -- see 'show off thread' for a recent mention), they may be able to affect the brew in a variety of ways. When people talk about pots rounding or 'erasing' aromas and flavors, I often think of catalytic decomposition as a likely mode of operation.

[Bob_McBob]

It would be interesting to see this clarified. Personally, I think that the only properties of a pot that impacts the tea is the thermodynamical properties, and whether it is beautiful.?

These are certainly the two most readily apparent differences. The shape, clay thickness, pour time, and other physical characteristics all significantly affect how the tea brews compared to using a gaiwan. Aesthetically and functionally pleasing teaware also significantly enhances a brewing session, even if it doesn't change the actual physical taste of the tea. I am reluctant to attribute any magical night and day taste difference to specific clays, though there are certainly enough clearly bad combinations to discount the effect completely.

[wyardley]

You are probably right.

Let me know as soon as your scholarly research is published, because I'm very interested to read it.

[MarshalN]

I have no doubt that other clays exist that are just as good, if not better, than Yixing clay for the purpose of brewing tea.

While we're at it though, other things also need to be considered, such as the firing temps, particle size, heat retention, etc etc.

[Tead Off]

Don't forget that China is an ancient culture (10,000 to 4,000 B.C. → Painted Pottery) with deep roots in Taoism whereas France is not.

Start to examine and explore Taoism/Daoism and you'll approach Yixing pottery from a different perspective. Lab tests can't examine the level of consciousness that Qi brings about in Yixing pots.

I think this is exactly why he is trying to separate out fact from fiction.

[tingjunkie]

What it all boils down to for me is this...

I can taste the difference, smell the difference, and feel the difference in my mouth. Notice that sentence was 100% personal to me. When I go to drink tea, there is no lab equipment in my mouth, or guys with lab coats and clipboards. So why would anyone need scientific tests to prove Yixing clay's effect on anything? Like Bob Marley said, "who feels it, knows it." You either feel it or you don't, and no lab tests are required once you do!

If you are the type that needs scientific verification, you should probably stick to a gaiwan, and not drive yourself crazy. Happy tea drinking to you, and please let us know if you find any new exceptional teapot clays from elsewhere. I'm not stuck on tradition.