As the microwaves used to heat food bounce around inside the oven, they create patches of high and low intensity – and thus uneven levels of heating. The problem with soup is that it tends to be relatively gloopy (or ‘viscous’), slowing the diffusion of heat within it. As a result, some parts of the soup start to form expanding bubbles of hot vapour which can burst through the surface, making a mess. Stirring the soup halfway through often solves the problem.
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- Why doesn’t a Cadbury’s Flake melt in the microwave?
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- Can microwaves change the molecular structure of food?