Technically, you can freeze McDonald's ice cream, but it is not recommended. McDonald's soft-serve ice cream is meant to be served immediately and consumed fresh. The quality and texture of the ice cream may change if you freeze it.
McDonald's soft-serve ice cream is made with a specific machine that dispenses a mix containing dairy products and stabilizers to achieve its soft, creamy texture. Freezing it at home can result in ice crystals forming, causing the ice cream to become icy and less creamy when thawed.
If you have leftover McDonald's ice cream and want to save it for later, it's best to enjoy it as soon as possible after purchase. If you do freeze it, keep in mind that the quality may not be the same after thawing, and you might not get the same smooth texture you would when it's freshly served. Additionally, freezing and thawing ice cream multiple times can further degrade its quality.
For the best experience, consume McDonald's soft-serve ice cream shortly after purchase or consider alternative frozen treats specifically designed for home freezing.