What does dry ice to to ice cream besides freezing it faster?

The main reason for using something like dry ice is because of the speed in which it freezes the ice cream. The faster it freezes, the smaller the ice crystals, and the smoother the texture.

This is why thawed ice cream that’s refrozen in your freezer ends up so icy because it freezes so much slower than even a traditional machine, and has large ice crystals.

However, you may be thinking more about liquid nitrogen, which is used by some ice cream shops lately. Dry ice is harder to use because it leaves chunks in the ice cream that don’t melt (or “sublimate”) right away. Liquid nitrogen produces an incredibly smooth texture that I’ve never had from any factory or traditional machine.