Did you find some rotten meat in your fridge or vegetables growing green fuzz?
As someone who hates wasting food, I can understand why you might want to try to sterilize spoiled food by cooking it.
However, cooking spoiled foods is not safe. Here’s why.
Is It Safe to Eat Spoiled Food If You Cook It?
Cooking at very high temperatures will kill bacteria and other microbes responsible for food poisoning. However, many microbes produce spores and toxins which are heat resistant. These spores and toxins can make you very sick.
Because you can’t know which microbes are on the spoiled food, it is not safe to eat spoiled food even if it has been cooked. On top of that, spoiled food will still taste disgusting after being cooked.
What Happens When You Rotten Meat, Moldy Food or Other Spoiled Food?
Spoiled food can make us sick in two ways. The first is by the microbes themselves. These can colonize the body and cause an infection. The second way is from toxins produced by the bacteria.
When ingested, these toxins can cause serious health effects. In addition to food poisoning symptoms, bacterial toxins can cause severe damage to the nervous system, organs, and other tissues. In some cases, bacterial toxins can cause death.
It Takes a Large Number of Bacteria to Make Us Sick
All food contains some amount of microbes on them. However, we don’t always get sick when we eat them. This is because it takes a relatively large amount of microbes to make you sick. The amount varies depending on the type of microbe and the individual’s health.
Unfortunately, it’s impossible to tell how much bacteria and microbes are in a food just by sight or smell. Food can look and smell fine and still have enough microbes to make you sick.
Does Cooking Rotten Meat or Spoiled Food Make It Safe to Eat?
Most bacteria are killed by cooking, so cooking spoiled food theoretically can make it safe to eat.
However, spoiled food which has been cooked is still not considered safe to eat. The reason is that some bacteria are heat-resistant or form heat-resistant spores and toxins.
Bacteria Die When Cooked
Most bacteria will die at temperatures of 212°F, which is the temperature of boiling water. Many types of bacteria can withstand extremely high temperatures, though. Luckily, most heat-resistant bacteria are not commonly found on food or are responsible for food poisoning.
Spores from Bacteria Are Heat Resistant
While bacteria die when cooked, many produce heat-resistant spores. As discussed in the FDA’s Bad Bug Book (PDF), these spores are in an inactive “survival mode,” making them very tough.
The spores themselves usually won’t make you sick, but after cooking, the spores can grow into active bacteria, which in turn make you sick.
Bacteria Also Produce Toxins
Some bacteria also produce toxins that can make you very sick. The most notorious of these is the botulism toxin, which causes death. Luckily, botulism toxins are inactivated at 185 F (below boiling) or boiling for 10min. However, other toxins are heat-resistant and could survive cooking.
Some examples of heat-resistant bacteria and spores:
- C. botulinum
- S. aureus
- B. cereus
- C. perfringens
Bacteria are not the only thing that makes food go bad. In dry foods like bread, it is usually mold that causes spoilage. Mold is easily killed at temperatures of 160°F. However, like bacteria, mold can produce heat-resistant toxins.
The most notorious mold toxins are mycotoxins and aflatoxins, linked to long-term health effects and cancer. Cooking will kill some of these toxins but not all. Mycotoxins can survive temperatures of over 350°F, and aflatoxins survive temperatures of 582°F.
The Food Will Still Taste Gross
Microbes in food cause it to break down. Even if you heat rotten food to high enough temperatures to sterilize it, the food will still taste rotten. On top of that, your kitchen will smell terrible if you cook rotten food (especially rotten meat).
Eating Spoiled Food In a Survival Situation
If you were in a survival situation where you had nothing to eat but rotten food, then, yes, it would be wise to cook the food before eating it. Ideally, you would cook it at very high temperatures and not just boil the rotten food. To do this, you’d need a pressure cooker.
The best-case scenario is that there weren’t high amounts of heat-resistant spores on the food, so cooking it effectively sterilized it.
Worst case scenario? You get struck by a severe case of food poisoning, end up with vomiting and diarrhea, and die a terrible death of dehydration or worse.
Also read: Best Food Preservation Methods
Unless it is an actual survival situation, it’s not worth the risk of eating spoiled food. Do a better job of keeping track of food in your pantry and fridge, so it doesn’t go bad. If you can’t eat it before it goes bad, then get it into the freezer. (Also read: Does freezing kill bacteria in food?)