If you define a foam as "a substance that is formed by trapping pockets of gas in a liquid or solid", a roti is absolutely a foam. Or, a foam subunit. (When yo

If you define a foam as "a substance that is formed by trapping pockets of gas in a liquid or solid", a roti is absolutely a foam. Or, a foam subunit. (When you make roti, it usually expands like a balloon during the cooking process.)