why is it if I cook something that’s about to go bad, it extends its shelf life?


For example, I have ground beef that’s turning bad. I cook it, and now its ok to eat the spaghetti Bolognese you made with it for the next three days?

In: 1

Bacteria is always growing in food. When we say a food has ‘gone bad’, it is because that bacteria has grown enough for it to effect the food and our bodies. Cooking food at a proper temperature kills a lot of the bacteria in the food and therefore sort of resets the timeline. Things like ground beef also foster a better environment for bacteria than cooked ground beef does.

Because cooking food kills the bacteria (70-odd °C, depending on time spent at that temperature). 3 days is then the recommended time under refrigeration before bacteria build up to harmful levels again. The reason you can’t just keep repeating this (and why endless stockpots are no longer allowed in commercial kitchens) is that bacteria will also produce toxins, which cooking won’t destroy.

Most food doesn’t “go bad,” it just “tastes bad” after some time.

Meat that has been frozen for a year in the freezer will become freezer burned and taste like cardboard, but it can still be consumed.

Cooking it will kill the bacteria, so it won’t spoil as fast, but it can still taste bad.

It depends. We can be negatively affected by 2 things regarding bacteria: a high amount of bacteria “invading” our GI system and throwing things off, and (primarily) by the toxins bacteria release when they die.

If you let food spoil, it’s hit one of those points. Cooking it before it reaches that point temporarily stops and resets the bacterial growth. It doesn’t remove the toxins though, just kills all the bacteria. Eat the cooked food within a few days and you can avoid the second round of bacteria growing enough that their combined toxins will overwhelm your GI system.

With that, if you cook some ‘turning bad’ beef that’s already at say…80% of your GI system’s threshold for toxins, you will have a shorter window for it staying safe to eat after cooking.