Lately I’ve been eating a lot of microwave meals (Lean Cuisines, Smart Ones, etc.) And I’ve noticed on all of them, the final “step” in the cooking instructions is to leave it in the microwave (after it has stopped) for 1-2 minutes before taking it out.
What is the purpose of this step? It occurred to me that it might be as simple as preventing idiots who don’t realize that those little plastic trays get hot from burning their hands taking it out. But if it was a true cya-type thing, wouldn’t they be more likely to put some explicit warning that the tray is very hot, rather than try to trick us into not touching it?
Or is there some other reason that you wouldn’t want to take it out right away?
Great username/topic combo. I think with some of those types of dinners that they continue to steam a bit, finalizing the cooking process. If you open them right away they’ll be drier and less appatizing.
WAG: Foods continue to cook (or reheat) through built up heat and built up steam. Why they say leave it in the microwave (as opposed to leaving it on the counter) could be because the m’wave is a slightly sealed environment, trapping hot air and moisture in a way that the countertop doesn’t. Perhaps the directions are calibrated to the test kitchen’s procedures?
Microwaves sometimes tend to heat unevenly, and I think it gives it a little time for the hot spots to dissipate and even out. It’s not good when you think “Oh, it’s perfect temperature” and then your next bite contains a ball of molten lava. I suppose this could also be accomplished by stirring, so shrug. I admit to having neglected the “standing” time before (in the microwave, and with frozen pizzas from the oven), and I’ve burned my tongue both ways I’m sure.
ETA: beaten to it. I also agree with the “continue to steam a bit” hypothesis.
Another reason is that those trays can be very soft and prone to spilling the contents. Upon standing they cool down and stiffen, making them easier to handle.
It might also have to do with nucleation. I remember reading that one problem that crops up with microwaves is that if you boil water in a microwave, you can actually heat it to the boiling point without there being very much in the way of visible boiling. Then if the container you are using is agitated (say, by picking it up), new nucleation sites are created, the water roils up, bubbles up, and can splash out of the container and potentially injure that person.
That’s only true if you heat fairly pure (distilled) water in a very clean, very smooth surfaced vessel, like a laboratory beaker or a smooth sided glass. Any bumps, scratches or mars in the finish or minerals in the water will provide plenty of nucleation sites for regular boiling to occur.
Seeing as a microwave dinner is chock full of nucleation sites like grains of rice, chunks of carrot and slivers of mushroom, superheating is not really a concern.
Evening out of the heat and preventing steam burns is, though, and both of those happen if the food is allowed to sit for a minute or two before handling.
Thanks for all the responses – the evening out of the heat and letting the steam dissipate makes sense. I suppose you could do the same thing by leaving it out on the counter, but maybe they figure that since you’re not going to eat it for a couple minutes anyway, there’s no point in risking a burn to your hands (whereas after cooking something in a conventional oven, you have to take it out because the oven doesn’t cool down the moment you shut it off).