Botulism is one of the scariest and most lethal foodborne illness infections. The bacteria Clostridium botulinum produces a toxin as it grows. A tiny, tiny amount of that toxin is enough to kill an adult. So how do you know if you have a botulism infection?
Most people think that botulism outbreaks are tied to canned food. It’s true that the bacterium grows in an anaerobic environment, which means that there is no air in the container that holds the food. But botulism can also grow in honey, which is why babies under the age of 1 should never be given honey.
And a deadly botulism outbreak linked to nacho cheese sauce served at Valley Oak and Fuel in Walnut Grove, California in May, 2017 sickened 10 people and killed one person.
The bacteria and the toxin do not change how the food looks, smells, or tastes, and the texture is not affected. The only way to protect canned food against this toxin is to make sure that all canned food is made according to food safety regulations.
The bacteria produces spores as it grows that act as a protective layer. Under some conditions, the spores grow and produce the toxin botulinum. Those conditions are low oxygen or no oxygen, low sugar, low acid, low salt, a certain temperature range, and a certain amount of water. That’s why home canned foods such as meat and vegetables and cakes and breads are considered high risk. Uneviscerated fish over a certain size can also contain the toxin.
Clostridium botulinum can also grow and produce toxins in chopped garlic in oil, homemade flavored oils made with fresh herbs, canned cheese sauce, carrot juice, and baked potatoes wrapped in foil. Some botulism outbreaks have been linked to traditional Alaska Native fermented foods.
Symptoms of botulism food poisoning usually occur quickly. Most people start experiencing them within 18 to 36 hours after eating food contaminated with the toxin. But, some people can feel sick within 6 hours, and there have been botulism cases that occurred up to 10 days after infection.
These symptoms progress downwards through the body in a parallel manner. All of the body’s muscles are progressively weakened. Early symptoms of botulism food poisoning include double vision, blurred vision, and drooping eyelids. Then the patient will experience difficulty swallowing, trouble breathing, a dry mouth, a tongue that feels thick, and muscle weakness. Eventually paralysis spreads down the body and can make it impossible to breathe.
Anyone experiencing these symptoms needs to see a doctor or go to an emergency room as soon as possible. There is an antidote to the toxin, but it can only be given in a hospital setting.
To prevent botulism food poisoning, it’s crucial that anyone who wants to can foods at home follow safe home caning instructions in the USDA Complete Guide to Home Canning. This guide is 5 years old. You may want to contact the extension service of your state university system to get more updated information about home canning.
I’m glad you posted this, very timely with everyone spending more time at home cooking. Could you please do an article about homemade sourdough starter? Does it pose a risk of botulism? (Note that I do treat flour as if it were raw meat, since I’m aware it has recently started falling prey to the e. coli contamination scourge.) Thank you
Well that is an interesting question. Sourdough starter doesn’t pose a botulism risk, because Clostridium botulinum only grows where there is no air (like inside cans), but E. coli is a question. I’ll have to check on that with some experts.