January 19, 2023 4 min read

Best Temperature For Green Tea: Messages in the water

Tea drinkers fret a lot about the best temperature for the perfect cup of green tea.  If the water temperature is too cool, they worry, you might not get enough flavor from the tea - if it’s too hot, it might turn the leaves bitter.  Sometimes we can agonize too much about conforming to method; it rather takes the point away from taking time out for a mindful sip of healthy tea - don’t you think? 

Don't get steamed up

That’s why Ocha & Co always prints simple - but tried and tested - instructions on our tea packaging about the best temperature for our green tea.  Just follow those and you’ll soon be sipping delicious tea with one less thing to worry about. 

Our rule of thumb is that if you’re making tea for yourself at home, simply boil the water and then leave it to cool down - usually between three to five minutes -  to the temperature best suited to the tea. It’s what most casual tea drinkers in Japan have been doing for centuries.

...There's always a caveat, though

Formal ceremonial tea-making is an exception  - there are traditions that must be observed, after all. In that case, there’s debate about whether allowing a cooling down deoxygenates the water which, in turn, leaves the tea with a ‘flat’ taste (perceptible to only the most learned of tea connoisseurs, it must be said). To mitigate this, some ceremonial practitioners add a splash of fresh water to the boiled to re-oxygenate it. 

It’s small but significant details like this that make an authentic, traditional Japanese tea ceremony such a fascinating, and edifying experience. If you ever have the opportunity to attend one then snap it up  - it really is the highest level of the tea experience. 

A storm in a tea tea kettle?

Less formal tea drinking at home comes without as many ‘rules’ but there are interesting approaches to boiling water for the tea that you might, for fun, want to incorporate into your own tea ‘rituals’. 

It might call on a slightly different approach to boiling water, though. Especially if you’re British. 

If you’re reading this in the UK, it probably goes without saying that you boil your water with an electric kettle. 

Non-UK resident readers might not know this, but electric kettles have been a fixture - in fact, standard issue -  in British kitchens since at least the mid-1950s. They have one job, to boil water to 100 C, the optimum temperature to make Britain’s favorite beverage - black tea (which is usually drunk with milk and therefore referred to as ‘white’). 

While stove-top kettles are more common throughout the world (although thermostat-controlled kettles are becoming widespread)  the ‘whistling’ kettle of yore is purely nostalgic in the UK - you’ll rarely see on in use outside of a campsite. 

There’s an environmentally-centered argument that boiling water in an electric kettle saves energy over a gas-powered stove. It’s a long-contested belief, though; there’s a corner of the internet (a niche one, admittedly) that’s packed with claims and counter-claim.  

Certainly, an electric kettle switches itself off when it’s boiled. That might account for some, tiny, saving in energy, but it does make it harder to master one of the ancient skills of tea making...

How to "read" the water

The origins of ‘reading’ water are Chinese and based on observing the five steps towards boiling in a traditional cast iron kettle - in Japan, these are called tetsubin  - on a stove as it heats up. 

To see this in action you’ll need to take the lid off, obviously, or you might just want to boil the water in a saucepan. 

One advantage of being able to tell the temperature of water by sight is that you don’t have to wait for it to cool down before pouring it on your leaves. 

To learn how to do it takes some patience and close observation - and a little bit of trial and error - but it’s a nice skill to teach yourself and might soon become part of your daily tea-making and drinking ritual.  

The Song Dynasty philosopher, calligrapher, and politician Cai Xiang (1012-1067) was the first to publish the language of water in the, still definitive, book the Record of Tea in 1049. 

To make the rules easy to understand, Xiang used animal characteristics to determine the temperatures of water as it progresses through the stages from cold to boiling point. 

They are:  

SHRIMP EYES -  the initial tiny bubbles (about the size of, well, shrimp eyes). This means the temperature has reached circa 70 C (155 F), the perfect moment to coax delicate flavors from leaves without them ‘burning’ - this is a really good temperature for making Organic Kabusecha or Sencha. 

CRAB EYES - as the name suggests, the bubbles have grown larger and the temperature is about 80 C (175 F) You’ll start to see wisps of steam, too. This is a good temperature for our Organic Genmai Matcha 

FISH EYES - now the bubbles are noticeably larger and they’ll be rising to the top of the water. You’ll start to hear the boiling, too. The water is going to be at least 85 C (185F) and you’ll need to remove the kettle from the heat if you’re intending to steep most Green teas.

STRING OF PEARLS - now the bubbles in your water are taking on the graceful appearance of a string of pearls. It’s a steady rolling effect meaning the temperature is now between 90-95 C (195–205°F) and really good for black teas like Benifuki. 

RAGING TORRENT - the clue’s in the name, the water is angrily bubbling away and has reached 100 C (212°F). Again, this is a great temperature for black tea 

You can find all the optimum temperatures for brewing Ocha & Cos teas here 

The next time someone asks you how to make the perfect cup of green tea you can tell them, in all honestly, to listen to what the kettle’s saying.