this post was submitted on 10 Dec 2024
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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.
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.