Thursday, May 20, 2010

The Thermal Energy of Tea

Although all types of tea come from the same plant, they have very different thermal energies. The thermal energy of tea is influenced by either the teas inherent properties, production, and/or how the tea is prepared.

1- As the growing time of tea leaves increase, its thermal nature becomes warmer. This factor explains how first flushes or shincha, which grow in an explosion of spring growth, is cooler in nature than a second flush, wherein the tea plant begins a short period of dormancy and grows much slower. This factor also explains how teas grown at higher altitudes have slightly warmer thermal energy because the tea grows much slower at a higher altitude.

2- Chemically fertilized tea plants generally have a cooler nature than wild or organic tea plants. This is true because, generally, fertilizers stimulate the tea plant to grow quickly.

3- The older the tea tree, the more warmth the tea has. This explains how old tree puerh is much warmer than puerh from younger trees.

4- The part of the tea leaf used influences the teas thermal nature. A bud is cooler than a leaf. So more tippy puerh is cooler than puerh with mostly leaves. It also explains how earlier flushes that contain more buds are cooler than later flushes. Twigs and stems are warmer than leaves. So the more stems in a puerh cake, or the inclusion of stems in some Japanese teas, makes them warmer.

5- The higher level of oxidization during production, the more warmth a tea has. This factor explains how teas that aren't oxidized, such as green teas, have cooler thermal nature than higher oxidized, teas such as black tea. This also explains how oolongs, yellow teas, and black teas that are highly oxidizated are warmer than oolongs, yellow teas, and black tea that go through lighter oxidization.

6- Steaming creates a cooler thermal energy than pan frying during green tea production. This explains how Japanese teas, which use a steaming method, are cooler than Chinese and Korean green teas, which use a heated iron caldron during production.

7- The thermal nature is related to the colour of the tea. This is probably the most obvious indicator of a teas' thermal nature. Tea with blue, green, or purple colours and hues are cooler than tea with red, orange, or yellow hues or colours. The following is generally accepted- from coldest to warmest- blue, purple, green, yellow, white, orange, black, red. The use of colour as an indication of thermal energy can be used to assess the dry leaf, the colour of the liquid, and the thermal nature of the types of tea (ex. green tea vs yellow tea vs black tea).

8- The longer a tea is aged, the warmer the tea becomes. The older the puerh, oolong, or ddokcha, the more enzymes and micobacteria act on the tea, and the more heat it generates.

9- Roasting the tea before preparation, increases its warmth.

10- The hotter the water temperature used to prepare tea, the warmer the thermal nature of the tea. This explains how subtle green and white tea, which are optimally prepared with cooler water, have cooler thermal nature.

Understanding the thermal nature of tea is paramount to using tea as a medicine, balancing the energies of the body, and thereby insuring that the tea you are drinking is helping and not hindering your health.

Peace

10 comments:

Bret said...

Very interesting and it makes good sense. You've given me food for thought.

Matt said...

Bret,

Currently, there is no material in print or on the web in English about the thermal properties of tea. Hopefully others will find this information informative and practical.

Peace

ThatGuy7679 said...

Very interesting indeed! Have you ever written more specifically about which teas are best for certain seasons or situations? I imagine that the differences between yin and yang energy are such that certain types of people are more suited for certain types and that even certain times of the year are more suited for certain types. From reading your blog it seems you mention the great pairing of winter and yang energy teas. So then does that mean Spring pairs with very cool (shincha perhaps) and that Summer perhaps with Chinese greens or green oolongs? It's certainly interesting not just for the times of the year but also matching teas with certain characteristics of a person as well~ That would make for an interesting read!

Matt said...

ThatGuy7679,

Yes, your a bit a head of the game. One intends to follow up this post with posts on The Thermal Nature of Tea and the Seasons (Astrology), The Thermal Nature of Tea and the Geographical Region (Feng Shui), The Thermal Nature of Tea and Individual Constitution, and The Thermal Nature of Tea and The Treatmentology of Illness. One had to lay the foundation down first- here in this post before things get more specific.

To answer your questions,

"Have you ever written more specifically about which teas are best for certain seasons or situations?"

If you read most posts on this blog they hint at these things, thought one hasn't explained the complete theories clearly and explicitly. Sometimes it is wise to meditate on things for a long time, to acquire more personal experience with things, to study more exhaustively on things, and to hear more wonderful teachers before just blurting things out. One feels that this was the case and that, now, the time is right.

"I imagine that the differences between yin and yang energy are such that certain types of people are more suited for certain types and that even certain times of the year are more suited for certain types."

Yes you are right. These topics will be covered in more detail in later posts. You mentioned constitution, and season, but also geographical location, and current heath of the individual play just as important roles in deciding which tea is best. Also you specifically mention Yin and Yang- the yin/yang theory is a bit of a broader interpretation of thermal properties which also includes other factors (like smell and taste-see this post -http://mattchasblog.blogspot.com/2010/05/yang-as-smell-yin-as-taste-yin-yang.html, and other things).

Although a multitude of theories can be used to choose the right tea, one will present each theory separately before mixing them all together.

"you mention the great pairing of winter and yang energy teas. So then does that mean Spring pairs with very cool (shincha perhaps) and that Summer perhaps with Chinese greens or green oolongs?"

Yes, its good to keep warm in the winter and cool in the summer but Spring, Fall, and the times of seasonal transitions are a bit more complicated. Everybody knows that spring and shincha harmonize well with each other but it isn't really because of the thermal nature of shincha, it is more to do with a different theory all together (will explain this one later too).

You are smart and get some of the deeper ideas. Feel free to ask more questions anytime.

Peace

Michal Tallo said...

Matt,
wonderful post!
I once again was able to learn something new from your blog. It, for example, really is true that during spring and summer, first flush teas and shincha are as it were all I want to drink, because of their cool character.
This changes later in the year - in fall, my demand of second flush teas increases, because they are somehow warmer.
So I really like the way you wrote it all up, it's very useful to see it all at one place. Thanks!

Sir William of the Leaf said...

I agree with you Michal.
There is always something interesting to learn from this blog!
I am still trying to get the concept of Cha Qi! haha
=]
Great post Matt!

Matt said...

Michal,

Sounds like you already harmonize the type of tea you drink with seasonal changes! Most people who listen to their body already do this without even being aware of it.

Peace

Matt said...

William,

Thanks for the kindness. Wonder if the Specialty Tea Institute even mentions "chaqi"? ;)

Peace

Bret said...

Interesting that Zero The Hero and I both posted today about the change of tea's correlating with the change of seasons. As you said, a lot of people do this by following their instincts. At least I know for me there is no intelectual decision on my part. Our bodies tell us what's, what. Sheng and most Oolong's get relegated to the Autumn and Winter months, they are just too heavy (warm natured) for my constitution.

Matt said...

Bret,

Nobody knows you better than you! If you just ask the question, "Why did I choose this tea today?" it will give you a lot of insight about what is going on inside of you and around you.

It is nice to put something more concrete out there explaining why exactly you are more likely to drink certain teas during certain times though.

You and Zero both mentioned seasonal influences in choosing your tea. Next thing you know all blogs will be including it in their tasting notes! That would be pretty interesting as it offers insight into a deeper faucet of tea drinking.

Happy tea drinking...

choose wisely (hahaha)

Peace