Choosing a Kettle: How Much It Changes the Taste

When people brew tea they tend to care a great deal about the material of the teapot, and the material of the kettle gets overlooked. If the kettle is made of the wrong material, no teapot, however good, will let you taste what the tea really has. Keep using a kettle of the wrong material and the teapot suffers as well.

For boiling water, I recommend a stainless steel kettle

I have used many kinds of kettle, and my conclusion is that a stainless steel kettle is the one to use. Most tea specialists in China use stainless steel, and about two in ten use glass. Like stainless steel, glass also tastes better the more it is used. Stainless steel covers a range of alloys, and the proportion of each metal varies with the grade. The taste differs considerably from one type to another, but it improves with use. One thing does deserve attention: a kettle sold as stainless steel sometimes has aluminium or copper inside. When that is the case, the body being stainless steel does not stop the taste from suffering. In China, even tea producers deep in the mountains normally use a stainless steel kettle.

Aluminium, copper, brass and silver do not suit tea

When you are drinking good tea, the materials I would avoid are aluminium, copper, brass and silver. They cut the finish and bring out astringency. The better a tea is, the longer its finish runs and the denser its aftertaste feels. That sensation is what people who love tea are looking for when they seek out a good tea, and a kettle made of one of these materials erases it. For anyone who wants to enjoy high quality tea, that is fatal. Copper is sometimes thought to help the taste. It does add fullness, and at the same time it cuts the finish and brings out astringency. With a lower grade tea or with coffee there is no real effect, because the drink had no fullness or finish to lose. Brass has atmosphere and looks handsome, and it still does not suit tea.

Why I do not recommend ceramic kettles

Another type I would steer people away from is the ceramic kettle. Many are on the market, mostly made in Taiwan, and walk into a Taiwanese teahouse and you will see them in ordinary use. They are beautiful to look at. Most of them are made without any thought for how the material affects the taste of tea. The majority add fullness while bringing out astringency and flattening the finish of the water. There are exceptions, and they are very rare. There is a further problem: keep brewing with a ceramic kettle and minerals from its material build up on the inner surface of your teapot, which degrades the teapot itself. In my experience the tea coming out of the pot declines within about a week. Switch back to stainless steel and the pot needs months of use before it recovers.

Iron kettles need care, and so does pairing them with a teapot

Iron kettles are generally believed to make water taste better, which is not always the case. They are not pure iron, and the alloy differs by maker. The material used to repair the inner surface differs by maker as well, and that affects the taste too. In my experience some iron kettles wipe out the finish, so it is wrong to assume every maker's kettle rounds out the water. When choosing one, keep in mind that the taste differs by maker, for better or worse. An iron kettle also has to suit the teapot you use with it. Some pairings work and some do not. When they do not, the water can taste better from the kettle alone than it does after passing through the pot, which is worth watching for. Given how tangled this gets, the safe course is to use a porcelain or glass teapot with an iron kettle, and to use water boiled in a stainless steel kettle when you brew in a ceramic teapot.

Ordinary electric water boilers are practical and taste good

One more that I do recommend, perhaps unexpectedly, is the electric water boiler sold by large makers such as Zojirushi and Tiger. Most of them can hold water at 98°C. Water boiled in a kettle has usually fallen to around 96°C by the time it is poured out, which makes the 98°C setting very practical. After long use, minerals build up on the inner surface, and the taste improves further. For that reason the scale should be left alone unless it interferes with the appliance working. To get hold of good tea I travel to the growing areas myself and put my effort into buying and processing it. When that tea is then brewed with tools made of the wrong material, its quality never reaches the person drinking it. People often conclude that the tea is what tasted poor, and that is hard to sit with. Anyone particular about tea tends to be particular about teaware, and I hope the points above are useful when it comes to choosing a kettle.