Can you cook botulism out of food?

In this brief guide, we are going to answer the question “Can you cook botulism out of food?”, discuss botulism, foods prone to botulism and preventive measures against botulism.

Can you cook botulism out of food?

No, you can not cook botulism out of food. You can kill botulism-causing bacteria (Clostridium botulinum) and the botulinum toxin by cooking. Heating the food at a temperature of 850C for 5 minutes will destroy the botulinum toxin and boiling kills bacteria.

But, you can not kill spores by cooking, as Clostridium botulinum is a spore producing bacteria. Spores will not be destroyed by just cooking, they are extremely heat resistant. 

They can withstand a temperature of 1000C for 6 hours.  

If spores remain in their inactive form after cooking they will not cause any problem but when suitable conditions are provided the bacteria will grow from spores and will produce toxins. 

So, Cooking may kill bacteria and toxins but it does not ensure the safety of food.

The only way to kill spores is heating at 1210C under pressure. To make sure that spores are killed,  commercially canned foods must undergo sterilization and home canned foods should use a pressure cooker.

What is botulism?

Botulism is a rare but dangerous illness caused by a toxin called “botulinum”. This toxin is produced by Clostridium botulinum (a bacteria). It attacks the nervous system and causes difficulty in breathing, muscle paralysis, and even death.

How does botulism occur?

It is not the bacteria that causes the illness but the toxin produced by it. This bacteria occurs in many places like soil, water but it is very rare for them to affect humans. Botulism occurs when the food containing botulinum toxin is ingested. 

These bacteria make spores that help them survive extreme conditions. Under favorable conditions, the spores germinate and form bacteria which produces toxins that cause botulism.

Conditions favoring spores to grow and produce toxins:

·   Low or no oxygen

·   Low acid

·   Low sugar

·   Low salt

·   Cooking temperatures that are too low.

Which foods are more prone to botulism?

Improperly processed foods especially home-canned foods or canned foods and low acidic foods with low or no oxygen are prone to botulism. 

According to World Health Organization (WHO) botulism toxin has been found in the following foods:

·   Preserved vegetables like spinach, mushroom, and green beans

·   Fish – canned tuna fish, fermented salted, and smoked fish.

·   Meat products- ham and sausages

·   Ready to eat foods in low acid packaging

Other food sources which may cause botulism include honey, corn syrup, oils infused with herbs, and cheese sauce.

How to prevent botulism?

Though botulism is a dangerous illness, it can still be prevented by taking precautions. Following measures should be taken to prevent botulism-

·   When home canning make sure to follow all hygienic practices(cleaning, washing, sterilizing)

·   Use pressure canners for low acid foods(potatoes, vegetables, meat)

·   Refrigerating any canned or cooked foods after opening them. (consume in 2-3 days)

·   Home canned food should be boiled for at least 10 minutes before consumption.

·   Maintaining pH below 4.6

WHO provides us with five keys to safer food-

1. Keep clean

2. Separate raw and cooked food

3. Cook thoroughly

4. Keep food at safe temperatures

5. Use safe water and raw materials.

Can you know if a food has botulism before consuming?

Yes, you can by observing the appearance and odor of the product  We can look for certain signs which can indicate that the food may be contaminated:

·   A leaking, bulged, cracked can

·   a can with a loose lid

·   food has a foul smell

·   rising bubbles surrounding fruits and vegetables.

·   Container spurs liquid when opened

·   Food is discolored

What happens when you eat contaminated food?

Botulism symptoms usually occur after 18-36 hours of eating contaminated food. It causes muscle paralysis which causes the following symptoms:

·   Difficulty in swallowing

·   Muscle weakness

·   Drooping eyelid

·   Blurry vision

·   Difficulty in breathing and moving eyes

·   Slurred speech

·   Vomiting

·   Diarrhea

·   Stomach pain


Cooking canned, low acidic foods does inactivate the botulinum toxin (at a temperature of 850c for 5 minutes) and kill botulism-causing bacteria (Clostridium botulinum)  by boiling. However, it can not kill the spores produced by bacteria as spores can withstand 1000c for 6 hr.

Spores are highly heat resistant; they can be killed only by heating at 1210c under pressure, this is known as sterilization.

So, cooking alone can not ensure food safety. It may inactivate the botulinum toxin but is unable to kill spores. 

These spores can grow into bacteria and produce toxins under favorable conditions (low or no oxygen, low acid, salt, and sugar).

Botulism is very rare but it is still a threat. It causes muscle paralysis and if immediate treatment is not provided may cause full-body paralysis.

In the end safety of any food depends on the hygiene with which we handle it and the application of good manufacturing practices.


In this brief guide, we answered the question “Can you cook botulism out of food?”,and also discussed botulism, foods prone to botulism and preventive measures against botulism.

If you have any questions or comments please let us know.

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