Why won’t microwaving spoiled food make it safe to eat?


My understanding is that the cells of bacteria and fungi are filled with water enclosed in a balloon. Wouldn’t microwaving then pop the balloons?

In: Biology

Microwaving it enough to ‘pop the balloons’ requires getting it above boiling temperature – something you won’t achieve with a brief microwaving. However, killing the cells is fairly easy by getting it hot (but not that hot) and basically re-cooking it. However, while the bacteria and fungi may be dead, any toxins they have produced will remain to poison you when you eat the meat.

Yes, but eating *some* bacteria isn’t what hurts you. Your stomach handles bacteria every day, surfaces are covered with them. However, when bacteria and fungi have been growing for a while on food, they’ve eaten some of it and, well, pooped. The toxins they release after they eat are designed to kill things, like other microbes looking to “share” the food that the current diners have found.

Penicillin is the poop of the Penicillium chrysogenum ~~bacteria~~ fungus, released to keep others from sharing the bread P.C. is living on. (Fun bonus fact, a relatives Penicillium roqueforti and Penicillium camemberti are used because we like the flavor their poop gives cheese.)

Enough microwaves to destroy these toxin molecules would virtually incinerate your food.

Edit: microbe type, oops

When food spoils it usually means that mold and bacteria have started to grow on it. While you can kill these if you apply enough heat for enough time, this won’t destroy the toxins they have produced, and those can still make you ill. In addition, microwaves work over a short time and heat up food unevenly, so there can easily be patches where bacteria survived.

You’re quite right about bacteria and fungi effectively being water wrapped up in a balloon (a cell membrane)! The application of heat (by microwaving or other heat like ovens) basically shakes apart the cell membrane, resulting in the cell ripping apart- think like how an earthquake shatters a buildings walls down.

This isn’t the be all and end all. The bacteria and fungi were able to exist and divide massively in your food because, well, it’s a food source! As time went by on the foods expiry date, the fungi/bacteria were able to rapidly divide and exponentially multiply. While they were doing this they were making various proteins to break down the food that they pumped outside of themselves and soaked all around the food.

These proteins are more temperature stable than living cells, and last on even after intense heating like cooking. These proteins are often toxins and are hazardous to you, me and many other animals that leave food alone for a bit too long. Evolution for us has prepared us for this by being able to detect rancid food and be scared off by it- hence why you often know something is off just by smelling it!

Hope this helps answer your question

microwaving heats food up killing the germs but germ’s poop stays there and can still make you sick.