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Botulism: What Home Canners Need to Know

I promote home canning to extend the availability of seasonal foods.  Home canned goods also happen to be delicious. There's only one potential downside: foodborne botulism.

Alex and I were talking about preservation yesterday in relation to someone we know who doesn't use salt, but is taking up charcuterie.   Bad idea, I say.

I had some questions about botulism that neither of us could answer so I dug through some internet and print sources to come up with this guide about the potential risks of botulism.

What I found is that botulism is not much of  a risk.  It is preventable, very rare, and curable.  That said, all of us who are preserving at home should be aware of the signs, symptoms, and prognosis of botulism poisoning.

What it is: a rare poisoning from proliferation of the bacteria Clostridium botulinum.  An average of 30 cases of foodborne botulism are reported per year in adults in America.

Causes: bacteria in the soil or untreated water, improperly canned food, especially vegetables, cured meats, honey, corn syrup.

Symptoms: difficulty breathing, swallowing and speaking, abdominal cramps, vomiting, weakness, double vision.  Symptoms begin 6 hours - 8 days after eating a botulism infected food.

Treatment: Botulinus antitoxin, breathing treatments.

Prognoses: Botulism is fatal in up to 60% of untreated cases.  Treatment is effective, especially when started quickly after symptoms begin.

Prevention during canning: Can to recipe specifications.  Be sure to use the advised amount of salt or acid and keep at temperature or pressure for specified amount of time.  Use current recipes from the Ball Guide to Canning.

Prevention after canning: Inspect canned goods regularly.  Discard any with disruptions in the seal, a bulging lid, one with pinprick holes, or rust on the lid.  Botulism toxin can be destroyed by boiling the canned food for 20 minutes.

How concerned am I? Not concerned.

I do many things that are far more risky than eating home canned food, like driving, being tattooed, road cycling, eating peas off the vine, etc.  I'm glad to know more about the very slight botulism risk and I will continue to enjoy and promote home canned food.