What is the name of cereal that makes a popping noise when you put it in milk?

There isn't a specific cereal that is known for making a popping noise when you put it in milk. This is likely because the popping sound is caused by air trapped inside the cereal getting released into the milk, which is a common occurrence with many puffed or crunchy cereals.

However, some cereals are more likely to cause this sound than others:

* Puffed cereals: Cereals like Rice Krispies, Cheerios, and other puffed rice or wheat cereals often have air pockets that can release when they get wet, creating a popping sound.

* Cereal with a crunchy texture: Cereals with a hard, crunchy texture, like granola or some breakfast biscuits, might also make a popping noise as the milk softens the exterior.

So, while there isn't a single cereal with a "pop" trademark, it's a fairly common phenomenon with many different cereals.