<<Disclaimer: Verify this information before applying it to your situation.>> I understand that not all brands of grated cheese are considered to GF, but I'm not sure why. We use Sargento GF brands at home, but I am wondering about having grated cheese when eating out. Is it the annatto color (which I believe is a not clearly a problem)? If so, what may be the problem with grated white cheeses like mozzarella?