If she hasn't eaten the babies yet, she probably isn't going to. I've only dealt with one cannibal (so far), but she ate both of her litters and another mouse's litter always within 1-2 hours after birth... Usually sooner than later.
If you see white, it should be milk in their stomachs--I can't think of anything else white on a pink's stomach... If I remember right, there was no other "white" in my pinks' bellies than the milk. If there's white, she's probably feeding them.
Try cooling her down with a fan if you think she's too warm, and just see what happens. Remember, the mother doesn't ALWAYS tend to her litter--unless you have a nest box that she has kicked them out of, I wouldn't worry about her being in a different location. After all, she has to eat and drink, too... During these times, the male or another female will normally babysit.