Everyday question
Can you boil water twice in the kettle?
© Shutterstock / Lilyana Vynogradova
You know this: You boil water for tea and coffee, but you have miscalculated the amount and now you have too much hot water left. What do you do with it now?
Just pour it away or bring it to the boil the next time and then use it? As the SGS Institute Fresenius found out, 53 percent of all Germans dump the water from the day before and do not use it any further.
The question of whether you can leave the water in the kettle has also been discussed in our bfriends forum for a long time. That's why we started looking for an answer.
Can I continue to use old water from the kettle?
The simple answer is: Yes. According to the Fresenius Institute, it is no problem to boil the water again the next day and use it for another cup of tea. There is concern that harmful substances such as nickel and bisphenol A could escape from the device and get into the water unfounded – provided the devices do GS seal for tested safety carry.
You don't need to be afraid of bacteria either. Because even if germs collect in the device, they would be killed by boiling them up again.
So doesn't it harm the water to store it in the kettle overnight?
No, you don't have to worry here. The Federal Institute for Risk Assessment (BfR) carried out an investigation into metals in kitchen appliances in 2015 and found that only minimal amounts of metal were released, which are far below the limit values.
This means that kettles do far better than coffee machines, for example. You should be careful here, especially after descaling: this is when they often release lead. This was not the case with the kettles tested.
By the way: If you regularly leave the water in the kettle, you have to Descale the device more oftenso that it doesn't break.
And what if I just don't like the water?
It is not always a concern for health when the water is dumped away from the day before. Some people just don't like the taste of stale water and find that it tastes "brackish". Then of course you don't have to use it and you can exchange it for fresh water. But the Fresenius Institute says: "The fear of stale cooking water is a relic from the time of immersion heaters and tea kettles."
We think: This is ultimately a matter of taste – and must be decided by everyone. What is certain is that it is not unhealthy or even dangerous is to leave the water in the kettle and use it later.