|MadSci Network: General Biology|
The temperature danger zone for food safety is from 40-140 degrees F. Perishable foods like milk are recommened to be limited to 2-4 hours in this zone. This time is cumulative, so if you warm a food, then cool it back down, and then warm it up again, the time adds up. Another rule of thumb in food safety is "when in doubt, throw it out".
I hope that helps.
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