Crust Encounters of the Third Kind
There was a time on the Italian peninsula where gruel-eaters ruled. The ancient Etruscans of Italy ate a thick porridge of spelt and hot water called Puls. Then three things happened to evolve this gruel. The first was that the Puls was increasingly cooked on the stones beneath the ashes of fireplaces. This unsalted ash cake was called Panis Focacius and was the ancestor of modern focaccia. Secondly, by 170 B.C. Greek bakers, who were brought to Rome as slaves, taught the Romans how to make a flatbread topped with “relishes” of herbs, onions, garlic and vegetables and had raised edges for better handling. And finally, unlike the Panis Focacius, this dough was cooked immediately after being formed and was called Picea, meaning “Black ashes on the floor of the fireplace.” Many generations of pizza-making have passed and the Picea is now known as “Pizza,” with crusts ranging from the soft mottled high-heat crust to the deep, dark golden crusts using refrigerated maturation.
Baby Steps
No matter what style, great pizza crusts are made by their creators with purpose, not by accident. There are several starting points, but the first step is to open your mind to all the different possibilities of baking pizza, then research and match your desired crust to your pizzeria’s capabilities. (The annual Pizza Expo in Las Vegas is essential in this endeavor.) The next thing to remember is that time and temperature are the most vital components in the perfect crust. Here are other factors involved in a great crust.
- The type of flour you’re using
- The hydration of the dough
- The mixing of the dough
- The fermentation of your dough
- The type of oven that you are baking with
Steam Clean
Crust formation is the result of loss of moisture in the baking process. As the pizza heats, water from the dough turns to steam and carbon dioxide, alcohol and other gases which escape into the air or are captured in the gluten net depending upon its strength. The longer the pizza bakes, the more moisture the crust will lose. This factor combined with the temperature of the oven and the hydration of your dough will determine the type of crust you will create.
Browning
Browning of the crust occurs when sugars, starches and proteins undergo changes. The sugars provide for caramelization and, what is called the Maillard reaction caused when the combined sugars and proteins, are put under high heat. Maillard is the browning of surfaces, be it meat or bread dough or pizza crust. There are several other factors that can ensure a colorful vivacious crust as opposed to a dull, flaccid crust. Fermentation and the use of pre-ferments are very important.
Blistering
Blistering is a thin, shiny, glass-like crust that sometimes looks like craters of the moon. Some pizza makers pride themselves on their blistered corniciones, (crust.) Blistering forms when Co2 escapes the surface of cold dough that is being held in refrigeration. The longer you retard your white flour dough under refrigeration, the more blistering you’ll have. (Whole wheat doughs blister much less.) The other factor in any blistering is the amount of steam in the baking chamber. This moisture may come from the pizza dough itself and depends upon the size of the oven. Too little or too much steam will inhibit the blistering process. I’ve known pizza makers who brush water on their ultra-aged crust before they bake to create blistering. When the dough is fully proofed, use minimal flour on the crust and gently wipe off the dusting of flour that remains because blistering isn’t cool looking if it’s covered with flour.
Spinal Tap
Pre-ferments added to a batch of pizza dough create the backbone of your pizza crust. These support elements have been used for many years and rely upon either lactic, (poolish) or acetic, (biga) fermentation to produce better flavor and the perfect crust. Modern bakers and pizzaioli have interspersed these additions to their doughs to produce a better product and increase production time as well as to enhance the color, taste and digestibility of pizza crust. (Note: as with all baking and pizza making, all measurements can vary and recipes for the perfect crust have been argued for centuries.)
Poolish: This is the batter-like pre-ferment made with equal amounts of flour and water and a small amount of commercial yeast to create lactic fermentation. This can be mixed from a few hours and up to a full day before adding it to a batch of dough.
Using an overnight poolish will create a pizza with better browning qualities producing a thin, crisp crust, greater extensibility, and a lighter texture with a sweet, milky, yeasty flavor. The bonus of poolish use is that it doesn’t take as long as stiffer pre-ferments and mixes easier into the batch of pizza dough as
opposed to the less hydrated pre-ferments.
Biga: This less hydrated pre-ferment is preferred by Italian pizza and bread bakers and is usually made with 1 percent cake yeast or .5 powdered yeast, water, and flour. It is mixed to a hydration level from 50 to 60 percent then set aside to let rise from 6 to 24 hours. Bigas made from a natural starter, called Biga Naturale, uses less yeast and a hydration level for up to 75 percent. The reward for this long wait to mature is a more complex flavor including a chewier crust, fragrant interior with sour notes, and larger alveoli (cells).
Pate’ Fermentee: This is a very old procedure and basically is old dough that has been fermenting and it is added to a new batch of dough. When I visited Paris, I found that this pre-ferment is a favorite of Parisian baguette makers, and they usually use up to 20-25 percent of their batch of dough for a quick and easy fortification. It can be used very easily by cutting up small chunks and adding it to your pizza dough as it mixes.
Direct Method Manipulation:
I am truly a big fan of the cold mix and long cold holding involved with the Pain a l’Acienne method made popular by my friend Peter Reinhart in his book Bread Bakers Apprentice. Cold water and cold holding halt the yeast activity letting the enzymes in the dough break down the complex carbohydrates into simple sugars. When the dough is finally proofed, the yeast starts to eat the sugars but leaves a sugar reserve which, when baked leads to a rich, buttery, wheat flavor, soft interior, and great crunchy caramel crust.
John Gutekanst owns Avalanche Pizza in Athens, Ohio.