How Did Botulism Get Into Nacho Cheese?

In order to get my feet wet in blogging again, I've chosen a topic that is in the news lately, at least here on the West Coast: tainted nacho cheese. Beyond thinking, "Who on Earth would eat gas station nacho cheese anyway?", here are some thoughts on the subject...

How did Clostridium botulinum get into nacho cheese? Oh, yeah, it was gas station nacho cheese, i.e. canned. You see, canning is a wonderful means of preserving food (in this case "food"), but if one does not raise the temperature of the canned foodstuff high enough in the canning process, then spores of anaerobic bacteria, like the Clostridium genus, germinate and grow rapidly in the oxygen-depleted environment.

Note on nomenclature for the uninitiated: the Capitalized name is the genus of the organism, like Homo in Homo sapien, and the second name, uncapitalized, is the species. Both are italicized by convention, or occasionally underlined. The genus is often abbreviated with the first letter. An example that comes to mind is E. coli; a species more often abbreviated than not, likely due to pronunciation issues for the genus, Escherichia.

The thing is, these bacteria also produce carbon dioxide in copious amounts, so contaminated cans typically outgas when opened. And I mean outgas! Hell, I had a can of tomatoes veritably explode on me once. Whomever opened that can or cans should have noticed the whoosh of gas escaping or they should have smelled the characteristic odor of C. botulinum, imho. Aren't food workers trained at all anymore?

Botulism is no joke at all. It is extremely deadly. The odds of dying with from botulism are orders of magnitude higher than for most other foodborne organisms. The genus has some really bad actors. Clostridium tetani causes tetanus, a disease that took my paternal aunt. Clostridium perfringens, like botulinum causes food poisoning,but is best known as the causative agent in gas gangrene. C. difficile is a common cause of a brutal diarrhea.

But in spite of these bad actors' in the genus, Clostridium species have many positive uses as well. Botox, of course, but far more that that cosmetic for the expressionless. They help us make paper and were fundamental to the development of smokeless gunpowder a hundred years ago (ask me if you want to know how that came about). Where botox comes from botulinum, an enzyme used in debridement of wounds, collagenase*, is harvested from Clostridial species, as are other enzymes in bioresearch. It's a fascinating genus, but stinky.

*Another note for the uninitiated, enzymes' names are produced by basically just adding -ase to the end of the thing they are active against (or with, depending on point of view) so, for example, if you want to know what the target of collagenase is, it is collagen. It's not always THAT simple, e.g. hyaluronidase and deoxyribonuclease target hyaluronic acid and deoxyribonucleic acid, but it's still pretty simple.

The article linked here didn't really say how the botulism got into the cheese sauce, and I haven't either. I'll rectify this oversight. The cheese sauce was "canned" cheese, but canning these days does not always use a metal can. Modern plastics and sterilization methods allow canning in bags and trays, e,g, the Hormel products I keep around for emergency nutrition (they're not bad, but they are not good, either).

Simply put, the spores of lots of different bacteria are all around us. Were you to place an appropriate (selective) agar plate on your kitchen counter, with the lid off for a few minutes, then incubate in anaerobic conditions, odds are you'd get Clostridium organisms of a variety of species to grow. It is safest to assume that all foodstuffs are contaminated with botulism spores when processing. Somebody either did not validate the sterilization process properly, or the minimum sterilization parameters were not met in processing, or the sterile barrier was breached in shipping and handling, which would mean that the packaging was not properly validated. In short, somebody is likely going to lose a lawsuit (or settle out of court).