Q: What is Calcium Carbonate?

Calcium carbonate is a specialty baking ingredient and alternative to sea salt found in the shells of many marine animals.

Why do we use it in our cereal?

Have you ever baked bread by chance? 

Sometimes when you bake bread (or anything else that "rises" / leavens in the oven), the rising does not happen evenly and you end up with a more "airy" crunch in certain parts of your bread and a denser crunch in other parts of your bread.

Calcium carbonate helps to even out the "rising" so it happens evenly across your bread.

Our cereal rises in the oven just like bread and so that's why we use it.