While early settlers were unfamiliar with the term artisan bread, they were more than familiar with sourdough, a staple on the frontier. The product was so common that prospectors rushing to the Alaskan Klondike gold fields were called ‘sourdoughs.’

A century ago, in 1910, 95 percent of bread in the U.S. was still made at home. As equipment manufacturers, ingredient suppliers and bakeries perfected mass production, this figure reversed itself, and by the 1960s, commercial bakeries supplied 95 percent of the bread eaten by U.S. consumers. Sourdough almost disappeared from the American scene, but small pockets of the country, most notably San Francisco, kept this artisan bread alive.

Traditional artisan bakers still create each loaf by hand. But how do bakers reproduce the sourdough bread experience in a wholesale bakery with a large-scale production process?

Beyond a simple matter of ingredients, creating artisan-style bread depends on the equipment used, including mixers, dough dividers/handlers and ovens.

The right tools

Artisan breads often are mixed in either spiral or oblique-axis mixers built solely to mix bread dough. These mixers employ rotating bowls, rather than the stationary bowls found in vertical mixers used for American pan bread.

Typical pan bread production involves a mechanical dough handling process for kneading, shaping and cutting that is too rough for lower-strength, higher-hydration artisan dough. To achieve high-quality hearth bread, bakers use newer style dough dividers for varied bread production that handle higher-hydration dough gently.

Artisan breads usually bake in deck ovens, with refractory bricking, which absorbs and reflects heat. In large-scale production facilities, sourdough pan bread is fed in a continuous stream on a conveyor belt through a tunnel oven with convection heat. According to Michel Suas, owner and president of TMB Baking, San Francisco, Calif., many tunnel ovens use a mesh conveyor that is “porous and pulls the moisture out from the bottom of the loaf. If you don't have a good bottom bake, the top will either be crusty and the bottom soft, or the bottom will pull up into a ‘dome shape.’” Tunnel ovens are designed with either stone or marble plates, 4 in. or 5 in. wide, to provide better heat transfer for the bottom of a loaf than a mesh conveyor. This style works best for those bakers who are set up for a continuous bake production, yet wish to conserve the traditional sourdough bread shape and texture.

According to “the Dough Doctor” Tom Lehmann, director, bakery assistance, AIB International, Manhattan, Kan., while sourdough production is possible in a tunnel oven with a standard conveyor, the process does create variances in the bread. “You lose that thick, crunchy crust characteristic.”

The ingredients

Traditional sourdough uses the action of lactobacillus — yeast from sourdough — or starters that either are active or can be reactivated. With the addition of grain products (flours) and water, they are capable of continuous acid generation.

It actually is the method of production that defines true sourdough — it doesn't have to taste “sour” at all. Bakers can control the flavor, finding a unique balance between sweet and sour. The process of discovering and identifying sourdough cultures is far from over, and each culture house offers its own blend or selection of strains.

Bakers also can create their own sourdough, called levain. This is a seven-day process of first capturing the wild yeast, breeding and then feeding and concentrating the yeast, notes Werner Simon, global bakery consultant for Caravan Ingredients, Totowa, N.J. All yeast cells and bacteria from the starter must be kept in a dark place to ferment in a controlled manner.

The problem with this process, notes Lehmann, is that the baker has no idea what sort of flavor is going to develop. “A native or wild culture could bake up good or bad. If it is good, you're home free, but if not, then all the equipment has to be sanitized and you start all over again. When you buy a culture, someone has already done the work for you, and you get a clean culture without background bacteria and one with a proven track record.”