The star ingredient responsible for an airy, bubbly pizza crust is yeast. As cells that eat sugar and convert into carbon dioxide, yeast is what makes dough rise -- yet Italian scientists have discovered a way to make pizza dough without it.

Because of a severe yeast allergy, Italian materials scientist Ernesto Di Maio can't eat traditional pizza, which is a tough deck of cards to be dealt while living in the birthplace of that iconic dish.