My fridge isn't working so I've been leaving the milk out on the counter. The regular pasteurised cow's milk has been going bad rather quickly. Lasts about 4-6 hours before it builds up that unappealing sour smell and a bit longer before it gets to that lumpy stage. I decided to buy goat milk instead and noticed it lasts waaaaay longer. Bought it yesterday evening and it's still drinkable now a day later. The only thing I can think that is causing this besides the differences in milk are the containers. The cow's milk is in a plastic see-through container and the goat milk is in a carton. I imagine the light participates in bacteria proliferation somewhat, but are there any inherent differences in the milk that would account for the shelf-life? If so, wouldn't goat milk be a superior form of dairy for people with bad digestion?