Different types of tea need water at different temperatures. Using a thermometer guarantees precision, but it can be a hassle and takes away from the relaxing vibe we want in our tea ritual. Do we really need to heat the water to an exact degree? I did an interesting experiment to find out about tea brewing temperature.
How important is the water temperature when making tea?
Except for the type and quality of tea itself, other parameters are absolutely important among which is tea brewing temperature.. Dark teas (black, oolong and PuErh, especially fermented-aged, in flakes or pressed into plugs, cubes or miniature cookies) withstand higher water temperatures (95-100 ºC), white 90-95 ºC. Compared to them, water for green teas varies between 50 and 80 ºC.
It's definitely a good idea to follow the instructions you get when you buy tea... at least at first. As you get better at making tea, you'll notice that you can prepare the same tea in slightly different ways and bring out what suits you best, whether it's the aroma, flavor, texture, or something else. In other words, you'll play around not just with the tea-to-water ratio but also with the water temperature. So, it's important to know how to answer the question: Do you know how to boil water correctly for tea?
Let's be clear, tea will benefit your health no matter how you prepare it, but why not enjoy all its qualities while drinking it? In other words, besides improving your health tea also brings numerous other positive effects.
If ”you overcook” it will be bitter and will not have a pleasant aroma. On the other hand, it can be too weak. As a result, perhaps you feeling like you're only drinking hot water.
On the contrary, if you prepare it in a suitable way, you will enjoy its taste, aroma and texture. In addition, you will also enjoy the ritual of preparation. Moreover, rituals are essential parts of human life.
How is the water temperature determined?
By observing water and as its behavior changes during heating, we can very precisely determine its temperature, which is truly of great importance when preparing tea. There are three basic parameters that should definitely be taken into account.
Back in 780 AD, the tea master Lu Yu, wrote about three stages of boiling water in his masterpiece "The Classic of Tea", initial, stronger and wildly agitated.
In the initial stage, small bubbles the size of fish eyes rise to the surface.
Next, in the stronger stage, the bubbles get larger, resembling crystal balls tumbling in a fountain.
In the third, wild stage, as a result of full boiling, the water bubbles vigorously in the kettle.
In some translations, the bubbles in the first stage are described as crab eyes, and only in the second stage as fish eyes.
According to Lu Yu, water at the medium boiling stage is definitely the best for making tea.
Besides observing the bubbles, it's equally important to listen to the water and observe the steam.
- Listening to the water
- Observing the steam
- Shape and size of the bubbles
Listening to the water
YOUNG WATER – Water that has just started to make sounds, "murmuring," is considered half-ready by Lu Yu and is not yet suitable for making tea.
MATURE WATER – When the water begins to "gurgle" loudly, it is the right water for tea.
OLD WATER – When the water transitions from loud gurgling to "wild bubbling," it is not used for tea.
Observing the steam
MIST – In the initial heating stage, a light mist rises above the water surface. At this point, the water is not yet ready for tea.
UNBROKEN COLUMN OF STEAMA – – When the steam rises vertically in an unbroken line, it indicates that the water is definitely good for making tea.
CLOUDS OF STEAM – When numerous clouds of steam start rising from the water surface, the water is no longer suitable for making tea.
Bubbles
CRAB EYES – Many small bubbles, like crab eyes, rise to the water's surface. This water is not good for making tea.
FISH EYES – Small bubbles gradually disappear, and larger ones, compared to glass beads or crystal balls, rise to the water's surface. Water at this temperature is definitely right for tea.
WATER "OLD WOMAN"– More and more large bubbles continuously "pop" and agitate the water ("wild water"). This water is definitely not suitable for tea.
In Russian tea traditions, the behavior of water heating in a samovar is described almost in the same way. When the water in the kettle boils, the lid loudly alerts us with its clattering, leading to the saying: “At first, the lid rustles, then it gurgles, sings, and finally roars.”
Over time, as the method of preparing tea in China developed further, from powdered tea to delicate green teas, from the T'ang dynasty to the last Chinese dynasty of Qing, the three stages of boiling water evolved into five stages. From "fish eyes", "pearls of glass" and "agitated water", during the Ming dynasty it became: "shrimp eyes" (very fine bubbles), "crab eyes" (fine bubbles), "fish eyes" (small bubbles), "connected pearls" (continuous bubbles) and "agitated water"
Experiment
Not wanting to undermine the undeniable authority and knowledge of the great master, whose advice is still used today, and prompted by the many questions that arose for me, I decided to conduct an experiment in hopes of clearing at least some of the question marks hovering over my head.
I heated the water in a cast iron teapot. After the water had completely "gone wild", I poured it into a thermos bottle and two gaiwans of the same volume. One porcelain and the other with thick glass walls, resistant to high temperatures.
The results of the experiment are presented in the table.
| Ord. num. | Temperature ( ºC ) | Porcelan gaiwan time required to reach temp. – minutes | Glass gaiwan time required to reach temp. – minutes |
| 1. | 95 | ||
| 2. | 90 | ||
| 3. | 85 | immediately after streaming | immediately after streaming |
| 4. | 80 | 1 | 2 |
| 5. | 75 | 2 | 3 |
| 6. | 70 | 3 | 4 |
| 7. | 60 | 8 | 9 |
| 8. | 50 | 15 | 18 |
When water is poured into other containers, its temperature immediately drops from the heating temperature to a lower temperature. In the thermos, the temperature dropped to about 96 ºC right after pouring from boiling temperature. Over the next 36 minutes, the temperature fell to 90 ºC.
In my experiment, I used the definitely cheapest thermos I could find. I will write about different thermoses and how well they retain water temperature in one of my upcoming posts.
Next, in both gaiwans, the temperature immediately dropped to 85 ºC after pouring (see the table). The further drop in temperature and the time you need to wait are shown in the table. The water temperature that Lu Yu describes as optimal for brewing tea (medium boil) is around 95-98 ºC, which is good for dark teas. In contrast, water for other teas definitely needs to be cooled to a lower temperature.
How do you cool down the water?
We can cool the water in two ways: by waiting for the container we poured the water into to do its job and cool the water to the desired temperature, or by adding cold water (the faster method).
Cooldown time depends a lot on material what the container is made of, but also the shape and volume of the container (of course, a smaller amount of water in a large container will cool down faster).
In his book Lu Yu recommends adding cold water to "revive" heated water. In any case, it takes a bit of practice and a good understanding of your own tea equipment to know how much cold water to add. In fact, you should experiment a little and decide which method works best for you. In other words, which method yields better results.
In the second part of the experiment, I heated the water to boiling, then poured it into a high-temperature-resistant glass gaiwan. The next step was to add about 10% cold water from the total amount needed for brewing tea. In other words, for a total of 200 ml, I added 20 ml of cold water to the heated 180 ml.
The quantities don’t need to be exact in milliliters. With a little measuring at first, some math, and practice, you’ll quickly become a master. When pouring, the water temperature immediately dropped to 85 ºC, and after adding the 10% cold water, the temperature fell by another 10 ºC. In just a few seconds, I had water at a temperature of 75 ºC. If I needed a lower temperature, I would have added a bit more water or waited a little longer. The water from the thermos, at 95 ºC, dropped to 80 ºC in the gaiwan. By adding about 10% cold water from the total amount needed, the temperature fell to 70 ºC.
You can also cool the water in a container intended for that purpose, such as Japanese Yuzamashi. In addition, you can leave it to cool in the container in which it will be prepared tea, cups or gong dao bei – borrows of righteousness. Let's clarify, gong dao bei is the vessel into which you will strain the tea, if you prepare it in the gong fu way. In other words, you have achieved a double effect in one stroke:
- you heated the teapots (gaiwan or teapot), Tea so retains temperature, aroma and taste longer
2. cool the water to the desired temperature.
Water temperatures for making tea
| TYPE OF TEA | WATER TEMPERATURE AT WHICH THE TEA IS PREPARED |
| White | 90 – 95 ºC … 195 – 205 F |
| Green | |
| Japanese | 50 – 70 ºC … 120 – 160 F |
| Chinese | 80 – 90 ºC … 175-195 F |
| Matcha | 70 – 80 ºC … 160 – 175 F |
| Yellow | 75 ºC … 165 F |
| Dark teas (Oolong, PuErh, Black and ripened, fermented) | 90 – 100 ºC … 195 – 210 F |
The table lists the most common examples of how tea producers specify water temperatures for different types of tea. Of course, there are exceptions that are not mentioned here, as they pertain to various types of tea from different regions of the world, and it would be impossible to list them all.
CONCLUSION
Will you enjoying tea depends on many parameters, one of which is definitely the water temperature. There are two basic ways to control it: by interrupting the heating at a crucial moment and by cooling the heated water.
The method you choose to apply definitely depends on the type of tea you are preparing and the water temperature you need. The ancient instructions of Master Lu Yu can certainly serve as a good starting point.
For those who prefer a more casual, intuitive approach, this is absolutely the best way to enjoy the ritual of preparing tea.
On the other hand, if you don't feel like bothering with observing the water, you can use a thermometer. Finally, for the simplest option, you can get an electric kettle that allows you to easily set the desired water temperature.
Don't worry about perfect precision - one or two ml or ºC (F) more or less won't compromise the quality of the tea you're preparing or your enjoyment of it.
Cheers.
After this interesting experiment, you know for sure which tea brewing temperature to use.
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