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xkcd #3022: Making Tea
(xkcd.com)
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this post was submitted on 10 Dec 2024
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Water warmed in a kettle has much more even temperature in all points, which affects the brewing process. Generally, the more even the temperature is, the more consistent and rich is your brew.
I would consider microwave boiling as a makeshift method to produce a mediocre result when you need it anyway, not as a daily driver.
How does a kettle warm the water more evenly but a microwave doesn’t? When a kettle has it’s heating element only at the bottom but a microwave blasts the entire mass of water with energy because it sits on a rotating plate.
Exactly because of that.
Hot water moves upwards, and if you heat it from the bottom, you get a more even result than if you blast it from all sides.
Cold water falls to the bottom of a kettle and boils on the bottom. Microwaves can miss the bottom, possibly?
Boiling water mixes itself, also: no
I'm asking this from a place of genuine ignorance: how does the evenness of the heat distribution matter when microwaving a pure liquid? I'm familiar with the microwave's uneven heating qualities. I'm sure we've all bit into food that is scalding hot on the surface and still lukewarm at best in its interior. However, I've always presumed that is a product of microwaving a heterogenous, predominantly solid substance.
So, sure, the microwave applies heat unevenly to the water. But wouldn't the tiny little bits of water which get "over" heated simply diffuse their excess thermal energy into the rest of the homogenous volume in very short order? Furthermore,wouldn't an uneven heat distribution in a mug of water simply lead to convection currents flowing from hot to cold, therefore promoting a relatively even distribution?
The overheated particles will rapidly move upwards, which will lead to relatively even distribution in a layer, but uneven between heights.
In fact, in a large microwaved mug the difference between top and bottom can be as much as 6°C/11°F.
Using a kettle mitigates it for the most part, as it is the bottom that gets continuously heated, and the top is then naturally heated by the vertical currents of hot water, leading to a more even distribution.
Surely stirring the water in the microwaved mug and giving it another round easily solves this issue.
Microwaved water can sometimes explode after being disturbed by stirring or adding coffee/tea bag:
https://youtu.be/0JOxuS0SBHc?si=brwRSWznsjPxqo5C
Ideally 2 to 3 rounds, yes.
But at that point, isn't it easier to just buy a kettle? It doesn't require such manipulations, costs next to nothing and allows you to rapidly boil up to 1,5-2L (0,4-0,5 gal) of water for all your needs.
There's a good reason most of the (Western, at least, dk about other places) world uses them and considers them a basic piece of kitchenware.
In the US, kettles are supposedly much slower than a microwave or even a hob due to their grid.
Fair enough; but even then, American kettles can boil water at a very reasonable time (3 minutes for 1,5L?)
Still, I can understand how that extra minute alters the choice for many.