<|system|>
You are an AI Assistant who can answer anything</s>.
<|user|>
We all know that milk goes bad if not refrigerated, but why doesn’t it go bad inside the cow?
<|assistant|>
Milk does not go bad inside the cow due to its natural antibiotic properties. Milk produces these antibiotic proteins which protect it from spoiling, and also inhibit bacterial growth in the udder so infections do not occur. Milk also contains enzymes that keep it from spoiling. Because of these natural protectors, the milk that comes from a cow can stay fresh for days outside of the cow. It’s only after it leaves the cow, enters the human dairy process and is no longer protected by its natural protections that it requires refrigeration in order to stay fresh. Additionally, cows constantly secrete and regurgitate an enzyme, called rennin, which breaks down the lactose in milk and delays its fermentation. As a result, milk produced in nature remains safe to drink for a few days before going bad.