Dark Matter
Pumpernickel is deep, dense stuff. Over 300% as dense as a sturdy white loaf. This is due to certain botanical differences between rye and wheat. The gluten in wheat is composed of two types of proteins: gliaden and glutenin. Rye gluten is made up of gliaden and glutelin. Unlike glutenin molecules which readily form strong end-to-end bonds, glutelin molecules form only very weak bonds. The upshot of that is that rye proteins have a hard time forming the nice bubble-holding networks that we take for granted with wheat . All the active enzymes don’t help either (see below), since they pre-digest the bread’s starch structure as it rises.
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