How To Avoid Botulism When Canning At Home
Canning your own is a great, and healthy idea, if you know what you’re doing. Here are pointers for avoiding botulism.
Canning your own fruits and vegetables at home can be very enjoyable and has many benefits. But it can also bring an increased risk for foodborne illness.
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Although it’s a rare occurrence, botulism is generally associated with improper home canning, but may still be found in some consumer food products. It’s a serious illness that paralyzes muscles and can even lead to death.
Botulism is caused by the presence of a nerve toxin from the bacterium Clostridium botulinum — which does have some medical uses outside of being consumed. But if this toxin contaminates your food and is digested it can cause serious symptoms and side effects, according to registered dietitian Laura Jeffers, MEd, RD, LD.
“Unfortunately, something as enjoyable as canning can be very dangerous if you don’t do it properly or if you don’t know what to look for in canned goods you buy,” she says.
There are three main forms of botulism infection that occur naturally, generating toxic spores when food is not properly prepared — infant botulism, wound botulism and food-borne botulism.
Botulism doesn’t spread from person to person like the common cold, Jeffers says.
“You can only contract foodborne botulism for example by eating contaminated food that carries the botulinum toxin,” she says. “These have usually been home-canned, home-bottled or poorly preserved.”
Home-canned foods with low acid content such as asparagus, green beans, beets and corn can easily become infected with botulism spores if you don’t follow proper canning methods.
Other foods can be risky even if they’re handled by large manufacturers.
“Unusual problems involving chopped garlic in oil, canned cheese sauces, chili peppers, tomatoes, carrot juice and baked potatoes wrapped in foil have all been cited in botulism cases,” Jeffers says. There are also many other foods that need to be properly refrigerated after any handling or preparation. You can check the U.S. Department of Agriculture for a comprehensive list of additional food safety guidelines.
The only way to avoid botulism is to avoid eating contaminated food.
“And the only way to avoid food contamination in your own home is to keep foods refrigerated, throw out expired food products, and very carefully and properly follow the steps to can your food,” Jeffers adds.
The U.S. FDA, CDC and National Center for Home Food Preservation offers detailed and proper techniques for canning and food safety guidance.
In addition to those guidelines remember these important tips when you’re canning at home:
“According to the Centers for Disease Control and Prevention, foodborne botulism symptoms generally show up between 12 and 36 hours after you eat a food carrying the toxin,” Jeffers says.
Sometimes the signs can show up as quickly as six hours or as late as 10 days. Generally the more quickly the symptoms appear, the more severe the case will be.
The main signs of food-borne botulism include:
In infants symptoms of botulism can also include:
In some cases, doctors will need to induce vomiting or use enemas to cleanse your intestinal tract of any remaining botulism-laced food.
If you’re affected, you’ll likely need hospital care. Your treatment may include antitoxins to prevent or help you recover from respiratory failure and paralysis.
Doctors put patients with severe cases on a ventilator and prescribe intensive medical and nursing care during recovery.
Widespread occurrences of botulism are rare. Though uncommon, outbreaks can be a public safety concern because many people can be infected by the same contaminated foods.
“Generally these outbreaks will make their way to the public through multiple news sources and will offer specific brand or product information along with locations or sources of the outbreak if they’re available,” Jeffers says.
“If you’re experiencing symptoms or think you may have ingested contaminated food, see your doctor immediately.”