It's funny, when you look back in history books or American cookery books, one of the reasons that the quinces and cranberries are used so often is because of their natural jelling properties.
Alton BrownCooking is an observation-based process that you can't do if you're so completely focused on a recipe.
Alton BrownA meringue is really nothing but a foam. And what is a foam after all, but a big collection of bubbles? And what's a bubble? It's basically a very flimsy little latticework of proteins draped with water. We add sugar to this structure, which strengthens it. But things can, and do, go wrong.
Alton Brown