C. botulinum is an obligate anaerobe, requiring an environment that lacks oxygen. However, C. botulinum tolerates traces of oxygen due to the enzyme superoxide dismutase, which is an important antioxidant defense in nearly all cells exposed to oxygen. C. botulinum is able to produce the neurotoxin only during sporulation, which can happen only in an anaerobic environment.
I’ve never once seen it said that the toxin is destroyed by exposure to oxygen, and can’t find such a claim on Wikipedia. If getting rid of the toxin was as easy as stirring the crap out of food for a few hours, the universally prevailing advice wouldn’t be to avoid food in swelled cans like your life depends on it (which it does).
Ok, good to know, thanks for the convo. Probably wouldn’t have saved any lives, since I would have assumed the amount of stirring required to get rid of it all wouldn’t be worth the effort if it did work like that, but my understanding is better now.
Canned foods lack 02, so a contamination means the toxin builds up over time instead of breaking down quickly, which is how it is so widespread without constantly killing people.
The go-to methods of preventing C. botulinum multiplying in canned foods is pressure-boiling the food at high temperature for a few minutes and adding acid (i.e. vinegar) and/or salt. The first one kills the spores, the latter two kill bacteria emerging from remaining spores. If this doesn’t work too well, the bacteria multiply and start producing the toxin and the gases.
There are also the options of dehydrating the food with salt or smoking, or adding lots of sugar. But the former two are mostly done to meat, to my knowledge, and the latter one is just sweets or honey.
It’s certifiedly anaerobic bacteria:
I’ve never once seen it said that the toxin is destroyed by exposure to oxygen, and can’t find such a claim on Wikipedia. If getting rid of the toxin was as easy as stirring the crap out of food for a few hours, the universally prevailing advice wouldn’t be to avoid food in swelled cans like your life depends on it (which it does).
Ok, good to know, thanks for the convo. Probably wouldn’t have saved any lives, since I would have assumed the amount of stirring required to get rid of it all wouldn’t be worth the effort if it did work like that, but my understanding is better now.
Btw, regarding
The go-to methods of preventing C. botulinum multiplying in canned foods is pressure-boiling the food at high temperature for a few minutes and adding acid (i.e. vinegar) and/or salt. The first one kills the spores, the latter two kill bacteria emerging from remaining spores. If this doesn’t work too well, the bacteria multiply and start producing the toxin and the gases.
There are also the options of dehydrating the food with salt or smoking, or adding lots of sugar. But the former two are mostly done to meat, to my knowledge, and the latter one is just sweets or honey.