Health,  Tea Culture

Brewing Tea: A Geeky Deep Dive Into the Chemical Composition of Tea and How It Affects The Experience of Drinking Tea.

There are many naturally occurring chemicals in tea. These chemicals change as the tea plant changes. If we can do a little investigation into these organic chemicals, we can learn more about brewing tea. A huge component of brewing is in learning the specific tea you have. Seen below is a chart that gives a basic description of the chemical components of tea and how they affect flavor.

So, the catechins in tea impart bitterness and astringency. The amino acids in tea (mainly L-theanine) provide a fuller body and a subtle, water-like sweetness to it. Finally, the caffeine in the tea contributes to a bitter flavor in the tea.

Tea can very much be like cooking. Once you understand the basic framework of a recipe and its ingredients, you can alter these to suit your preferences. This is also true with tea. In fact, in the Chinese tea tradition, the brewed tea is literally called the chátāng (茶汤) or “tea soup”. Knowing this, let’s look at the different chemical components in tea to better understand of how we can brew our tea to suit our preferences.


We start with our friends the catechins, namely EGCG. Catechins are seen to provide us with a host of benefits. The longer the tea leaves stay in the sun, the more catechins they will develop. Brewing tea for a longer time will extract more of these catechins. With regard to drinking tea, catechins impart a bitter flavor and astringent mouth feel. Tea types grown in full sun such as bancha will generally are quite bitter and astringent.

Amino Acids

In terms of amino acids, the star of the show is here is L-theanine. L-theanine has been observed to increase alpha brainwave activity in the brain. This shows that it relaxes the mind without causing drowsiness. Higher quality tea will generally contain higher amounts of L-theanine. This is especially true of shaded teas like gyokuro and matcha because there is less catechin development in these teas. L-theanine contributes to a “fuller body” in tea; the tea can have an oily mouth feel and slightly sweet, fatty flavor almost like soup broth.


We’ve all probably heard of this one. Caffeine is the most widely used psychoactive substance in the world. Apart from giving us the nighttime zoomies, it also contributes to the flavor and body feel of a tea. It could be said that it is also a component of the cháqì (茶氣, “tea energy/life force”). This is a term used to describe the overall character of a tea and how it makes us feel.

Water Termperature

Increasing the temperature of the water used to brew the tea will extract more caffeine and catechins. This means that, when brewing tea, the hotter water, the more bitterness and astringency you will extract. This is mainly true for green tea. Other types of tea such as roasted tea, and post-fermented/dark tea will often not become bitter when brewed with boiling water. The L-theanine however, remains relatively the same. When brewing tea with cold water, that it tastes sweeter then a hot brewed. This is especially true of green tea. This most likely is because less caffeine and catechins are extracted when brewing tea this way.

Many people say, that green tea should be brewed lower temperature water to control the bitterness. This is mainly true for sencha and gyokuro, yet it does not apply to all green teas. So, you use a low water temperature to control the bitterness. Genmaicha, Kukicha, and Houjicha are teas where you want to enjoy the aroma as well as the taste, similar to oolongs and black teas. In these cases, brewing tea hotter water is often used.

Steeping Time

As mentioned above, the time spent brewing the tea also plays a big part in the experience of the tea.

Some Temperature Parameters when Drinking Tea

You can see in the chart above that there is a pattern of…

  • Hot Temperature, Short Steeping Time
  • Low Temperature, Long Steeping Time

In Chinese and Japanese tea culture, steeping times are kept relatively short (between 10-60 seconds). This is because it is thought that you can taste a tea through multiple short infusions.

When brewing tea, Hotter Temperature Water/Shorter Steeping Time will allow for a lot of flavor and subsequent infusions. Lower Temperature Water/Longer Steeping Time will pull out less bitterness in a tea, allowing for more sweetness and a thicker mouth feel. This is generally true of green tea and brewing tea of other types may not result in the same way (our Wakoucha Mariko brewed with boiling water will still taste quite sweet, for example.) If you drink tea partially because you like hot drinks, then the first method of brewing tea (hotter water/shorter steeps) would probably be the way to go.

Other Combinations

Here are some combinations not shown in the chart above:

  • Hot Temperature, Long Steeping Time
  • Low Temperature, Short Steeping Time

We recommend using a Hotter Temperature Water/Longer Steeping Time for those interested mainly in the health benefits of tea. This is because, with greener tea, the resulting brew will most likely be quite bitter. In the case of something like the Chinese tea shēngchá (more commonly known as sheng pu’er), sometimes brewing this way will make the cup almost hilariously undrinkable because of how bitter and astringent it is. Still, what you pay for in flavor you will receive in catechins and caffeine so to each their own.

If you try your hand at using Lower Temperature Water/Shorter Steeping Time, well, you might be a bit underwhelmed. Even really good tea will taste a little flat, almost giving you a teaser of how the tea will be if brewed the other three ways mentioned above.

The Importance of Motivation

Something that we as tea drinkers can reflect on is the reason why we are drinking our tea. When we talk about the experience of drinking tea, the motivation for why you are drinking it can very much determine how it makes you feel about the experience.

If you are drinking tea to bolster your health, for example, you might choose to drink high quality tea and worry less about the pleasure the tea provides (or lack thereof) and therefore not suffer that much at its loss. If you use tea to pursue sense pleasure only for yourself, especially to the point where you would disregard yours or other people’s welfare, then even with a brew that has a “perfect” balance of bitterness, astringency, and sweetness, would still leave you feeling mentally unstable, dissatisfied. You had tasted something amazing and now it is over and you wonder “what next?”

So, tea really can be such a beautiful means but, if seen as an end, the experience of drinking it can become unsatisfying and destructive. It becomes a beautiful means when we use it to preserve our health and sharpen our mind so we can be of further service to others. It becomes a destructive end when we drink it merely for the transitory pleasure of it. This leaves us unsatisfied, bereaved of the tea experience we held so dear.

With In this context, while tea contains caffeine, which is a stimulant, and L-theanine, which is seem to bring our brain into a state of calmness and relaxation, the motivation for why you are consuming the tea can very much make or break the experience. This could be something to consider. Either way, we hope you have found this blog post informative if not inspirational. Feel free to follow our instagram and tiktok. You can also subscribe to our newsletter by entering your email address in the designated area at the bottom of any page of our website.