How come some ice cream sandwiches don't melt in the blazing sun?

After hearing the news story about how a mother was concerned that her son's ice cream sandwich from Wal-Mart didn't melt after 12 hours in the sun, Dan Collins of KIKN 100.5 in Sioux Falls tested it out himself and recorded the process for video proof. Indeed, these things don't melt. But why? How is this possible? » 7/29/14 12:24am 7/29/14 12:24am