
Do I really need to leave my food to stand after it comes out of the microwave?
Ping, dinner’s ready! Or is it? Leaving your delicious microwaved meal to stand as the packaging recommends is an important part of the cooking process.
Microwaves only penetrate to a depth of around three or four centimetres, so anything deeper is heated indirectly, by conduction from the outer layers of food. The cooking instructions on a ready meal might say to heat it on full power for five minutes and then leave to stand for another two.
The first phase adds enough energy to cook your lasagne, but when it comes out of the microwave, that energy is unevenly distributed. Leaving it to stand allows the heat to make it to the centre, where it will kill off any bacteria. So always respect the instructions.
Read more:
- Is an old, but functioning, microwave likely to be dangerous?
- Can microwaves change the molecular structure of food?
- Why doesn’t a Cadbury’s Flake melt in the microwave?
- Is there an opposite to a microwave that can cool food instantly?
Subscribe to BBC Science Focus Magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun facts.
Authors

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
Sponsored Deals

May Half Price Sale
- Save up to 52% when you subscribe to BBC Science Focus Magazine.
- Risk - free offer! Cancel at any time when you subscribe via Direct Debit.
- FREE UK delivery.
- Stay up to date with the latest developments in the worlds of science and technology.