food “going bad” really isn't accurate enough in most cases
sometimes it means “becoming unsafe to eat”, usually due to microbial growth
sometimes it means “becoming unpalatable”, like fats getting rancid
sometimes it just means “changing“, like bread getting stale or milk getting sour, both of which are still usable as an ingredient
sometimes “unpalatable” is highly subjective, sometimes things thought to be unsafe to eat turn out not to be, finding that out and surviving is how we got most fermented foods today
and sometimes we just enjoy consuming actual poison…
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