Comment by BenjiWiebe

It may depend on the milk quality and the dairy. There's definitely a taste difference between our raw milk and our pasteurized milk, and neither one is bottled.

You can even sniff the pasteurizer and smell if it's the raw milk or if it's been pasteurized.

Also when making cheese, the naturally occurring bacteria and enzymes in raw milk make quite a large flavor difference (from a cheesemaker's perspective anyways).