Why Don't Ice Cream Sandwiches Melt?

An "ice cream" sandwich left in the sun doesn't melt. How is that even possible?

Image Credit: WCPO Cincinnati.

Cincinnati-area mom Christie Watson recently discovered that an ice cream sandwich, left uneaten on a sunlit patio table for 12 hours, had not completely melted. Unnerved, she took a second sandwich from her box of Walmart Great Value Sandwiches and left it out over night. Same result.

She took her concerns to Cincinnati news station WCPO, who repeated her experiment with a pint of Haagen Dazs, a Klondike Bar, and yet another Walmart sandwich. Half an hour in the hot sun reduced the treats to a puddle, a semi-solid, and a more-or-less intact "ice-cream" sandwich, respectively. WCPO contacted Walmart, who issued the following statement:

Ice cream melts based on how much butterfat and cream are in it. Our sandwiches contain less, and are more affordable. But they are healthy and meet all FDA guidelines.

So what do ice cream sandwiches have in place of butterfat and cream? A pint of Haagen Dazs contains just cream, milk, sugar, eggs, and vanilla. The ice cream in Walmart's sandwiches, according to the company's website, contains:

Milk, Cream, Buttermilk, Sugar, Whey, Corn Syrup, Contains 1% Or Less of Mono-And Diglycerides, Vanilla Extract, Guar Gum, Calcium Sulfate, Carob Bean Gum, Cellulose Gum, Carrageenan, Artificial Flavor, Annatto For Color

The things you find in Walmart's sandwiches that you don't in Haagen Dazs and other premium ice creams are what food scientists call "stabilizers." According to Ice Cream Geek, stabilizers help extend ice cream's shelf life, reduces iciness, and, yes, slows the melting process. So while those fillers might not account for much of the ingredients in Walmart's snacks, they're enough to help it hold its shape in the sun. They also lower the bars' price. According to WCPO, a pint of premium ice cream can run north of 3 bucks. For the same price, you can get a dozen of Walmart's ice cream sandwiches. What a deal.