Why would scallion oil go bad?

[Live_to_cook]

Thanks for taking the time here at ChefTalk.

Vegetable oil can sit in my cupboard practically forever.

But when I make scallion oil (slice bunch of scallions, drop in hot hot vegetable oil, drain) the recipe says it must be refrigerated and can only hold a few days. What gives?

[phatch]

Botulism. Look at the botulism thread in this same forum. You are using a wet ingredient that will support botulism growth in an oxygen free environment.

On the other hand, many recipe sources are extremely cautious to avoid any liability lawsuits. The Beef Council won't recommend any cooking method below 350 for beef even though Prime Rib is usually cooked lower commercially.

Phil

[Live_to_cook]

If you heat the oil past 300F, wouldn't that kill whatever bugs there are?

Edited to add: I mean, reheat it before using if it's been sitting around for a while.

[phatch]

Botulinin toxin denatures at 160 as I recall. The spores that create new botulism can take quite high heat and pressure.

Heating the oil repeatedly also causes it to break down and taste off too so while you're making it safe (for a time), you're also degrading flavor.

Phil

[Harold McGee]

No need for me to add anything! Phil is right on these points.

Harold