Darren72 wrote:Yes, botulism is possible with yogurt.
I'm not sure why you say that. I've been reading a bit on the microbiology of food fermentation (especially yogurt, sauerkraut
and crème fraîche
) and would say that botulism from yogurt is highly unlikely. There was an outbreak in Britain in 1989
but that was due to contaminated hazelnut preserves that had been added to the yogurt. Do you know of any other cases of botulism caused by yogurt?Clostridium botulinum
, the bacterium that causes botulism, generally doesn't grow below pH 4.6 (moderately acidic). Most yogurt is more acidic than that, one reason it's an inhospitable medium for most pathogenic organisms. Indeed, exclusion of pathogens is why yogurt has been a common mode of milk preservation for millennia. Most spoilage of yogurt is due to yeasts and molds, not bacteria.
I don't think you have to worry much about botulism from a carton of yogurt, even one with a bulging lid. That's not to say there isn't a potential hazard from other microbes so the safest course of action is to throw it out.