A TSA Supervisor in STL once took a gel-pack we were using to keep some breast milk cold, saying something like "Its only allowed for medication, not infants." After the milk spoiled, several TSA folks have agreed that he was mistaken, since the web site says breast milk is in the same category as medication.

The best you can get from TSA's website is this:
So if you put some refrigerated medical item next to your food you should be golden.