system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: We can’t drink spoiled milk but we can consume butter milk, yogurt, sour cream, cream cheese etc?

Why can we not drink raw milk or expired milk but we can consume various forms of milk mixed with bacteria/cultures?
gpt
The primary difference is the bacteria present when the milk is spoiling. Some are toxic and cause the milk to go bad. Some are not toxic and produce the yogurts and cheeses you know and love. When they make cheese for example everything is carefully sterilized first so the only bacteria present are the cheese cultures that are added. In your fridge there are all types of bacteria and the bad ones cause your milk to become unfit for consumption.