By Tabitha Alterman
The protein structure, or gluten, in baked breads is normally developed through lots of kneading. The Dutch oven technique requires no kneading, but the gluten does strengthen. Simply stretching and folding the dough in half a couple times throughout the rising, or fermentation, process strengthens its structure enough to allow a web of proteins to trap the gas produced by the active yeast. (Click here to watch a short video demonstration of the no-knead technique.) Allowing a long fermentation helps to trap even more gas, which creates the bread’s volume. It also gives the loaf enough time to develop organic acids fully, which imparts fabulous flavor.
It’s essential to have steam during the beginning of baking a loaf of bread. Yeast activity accelerates as soon as the bread enters the hot oven. If you put the dough in a dry oven, the crust sets immediately, preventing the yeast from expanding the bread. By using a covered Dutch oven with this wet dough, the all-important steam is trapped inside, surrounding the loaf. This keeps the crust soft and cool longer, allowing the yeast to go to work and the loaf to grow. Enzymes in the dough are also active at this time, particularly on the warmer surface, busily working to convert starches into dextrins and other simple sugars. These compounds contribute to crust coloration and flavor. Eventually (at about 140 degrees), the yeast die off. Then the starch granules absorb water, becoming swollen and glossy. This process is known as gelatinization, and lasts until the temperature is about 158 degrees.
By preheating the heavy Dutch oven before putting the loaf in, you replicate the direct heat of professional stone hearth ovens. The heat of a Dutch oven remains much more constant than the heat in a conventional oven. It also traps much more steam inside than can be achieved by putting a pan of water into a regular oven. Regular ovens vent, so it’s difficult to keep enough steam inside. Combined with a wet dough, the superhot pan traps plenty of humidity inside. Plus, the higher the internal temperature of the loaf, the more webbing and sheen will be created in the crumb.
When most of the moisture in the Dutch oven is absorbed, the crust reaches higher temperatures, becoming crisper and firmer. The sugars on the surface begin to brown, creating tremendous flavor. The loaf is finished uncovered to allow maximum heat and evaporation at the surface, and thus maximum development of the scrumptious crispy crust.
This handy chart from Bread: A Baker’s Book of Techniques and Recipes (John Wiley & Sons, 2004) will help you better understand what’s actually happening to a loaf of bread as it cooks. This excellent cookbook was written by Jeffrey Hamelman, director of the bakery and Baking Education Center at King Arthur Flour. Read our editorial recommendation of the cookbook here.
Photo: ROGER DOIRON