If you warm up whole milk prior to feeding a child and the child doesn't drink it all, can you save it by putting it in the refrigerator to warm up again later? Is this a bad idea?
I have done it with both of my children, and never had a problem. That said, we never let it sit more than half a day. Do make sure you seal the container though. Odor from other food in your fridge can get into it if left open.
Also note that pasteurization is nothing more than heating raw milk to a 161F and then cooling it back off.
If it looks or smells funky obviously you would want to throw it out. :)