I have read in many places 1,2,3 claims of a link between preparing foods sous vide and botulism, with claims that this is because the food is prepared in a vacuum.
This struck me as illogical, so I looked around online and could find no solid references to back up the claim that cooking food in a vacuum can result in botulism poisoning.
From what I can tell, there has been misunderstanding and confusion about the risk of vacuum sealed foods and botulism. I suspect it's because often vacuum sealing is performed to preserve food. In this case, fresh food is being vacuum sealed just before cooking to protect the food from the water, but still let it come in close contact with the water, after which it is immediately unsealed.
I also assume that clostridium botulinum does not thrive in a vacuum more than it does when exposed to air.
Is there any solid science to these claims I am questioning or is this a misunderstanding?