Can you get a deck-oven taste from your conveyor?

Q: We are new to air-impingement ovens, and I now want to begin developing a hearth-baked type of pizza. We have done some testing but all that we have been able to make is a crust that is crispy — it still doesn’t have the desired hearth-baked characteristics that I’ve seen coming from a hearth-type oven. Is there any way to make this type of pizza crust in our oven?

A: For a good number of years research has been going on to develop a hearth-baked crust characteristic using an air-impingement oven. We have found that a multi-faceted approach is necessary in order to successfully achieve the characteristics.

The baking time and temperature must be addressed, as well as the dough formulation and the baking platform itself. To begin, air-impingement ovens will need to be profiled in a pretty typical pizza profile with the bottom fingers fully open and most of the top fingers closed with just enough top heat to achieve the desired top bake to the pizza. With the newer generation ovens the baking temperature will be between 465 and 500 F with a baking time of 4.75 to 5.5 minutes. When an older generation air-impingement oven is used the finger profile remains the same but the baking temperature is normally adjusted to 500 F to 525 F with a baking time of around six minutes.

In order to bake the pizzas at this time and temperature without getting excessive crust color it is necessary to delete any sugar, eggs or milk from the dough formula since any of these will contribute to excessive crust color development under these baking conditions. These changes by themselves will contribute to a pretty nice eating characteristic, but the characteristic charring on the bottom of the crust will be missing, and to some extent, the finished pizza may have an excessively hard outer edge/crust, AKA pizza bone. To address these issues so that we can get the desired amount of crust char without developing a pizza bone, a special baking disk has been developed specifically for this application. When the formula changes are made and combined with the oven baking profile and special baking disk, it is entirely possible to achieve a hearth-baked pizza characteristic using an air-impingement oven.

Q: We occasionally get a gum line developed in the center of some of our pizzas, but not all of them. Do you have any guess as to what might be responsible for this sporadic occurrence?

A: The most common cause of this problem has to do with the way the toppings are applied to the pizza skin prior to baking. When saucing the pizza skin, take extra care so as to move any sauce away from the center of the skin leaving just a thin sauce layer in the center. Then as you apply the cheese do the same thing, taking care so as not to just dump all of the cheese into the center of the skin and try to spread it out over the surface of the pizza skin. Instead, apply the cheese so as to create a slightly thinner layer of cheese in the center of the pizza skin.

Don’t worry about the center of the pizza not getting a uniform dispersion of sauce and cheese. As the pizza bakes the sauce and cheese will flow back into the center section but not before the center section has had a chance to begin baking, thus eliminating the gum line from the center of the pizza.

Q: We have a very small shop with only reach-in coolers so we are not able to store dough balls from one day to the next. At times we have saved our last dough balls of the day to the following day and we really like the flavor of the finished crust. Is there any way we can get this kind of flavor in the dough that we mix and use during the same day?

A: Yes there is! The secret is in using an overnight sponge to develop and provide flavor, much like using a sour, but a lot easier to manage.

Begin by making a “sponge” or pre-ferment that will be allowed to ferment overnight. To size the sponge correctly use about five pounds of flour for each 25-pound bag of flour that you will use for making dough on the following day. Mix this with .1 percent instant dry yeast (IDY) based on the total flour weight and 50 percent (2.5 pounds for each five pounds of flour weight) of cold tap water, and mix just until it is incorporated (about five minutes at low speed). The sponge should be lightly oiled and covered with a piece of plastic to prevent excessive drying then allowed to ferment at room temperature for 18 to 24 hours.

To use the sponge, weigh a portion of the sponge (7.5 pounds for each 25 pounds of flour that you want to use — but remember to weigh out only 20 pounds of flour since there is already 5 pounds in the amount of sponge that you have portioned out). Add all of the regular dough ingredients, including the full amount of yeast to the dough, but reduce the water content by 2.5 pounds since there is already 2.5 pounds of water in the portioned out sponge. From this point on the dough is mixed and processed by your normal manner. The fermented sponge will provide a level of both dough conditioning and enhanced fermentation flavor to the finished crust.

Tom Lehmann is a former director at the American Institute of Baking in Manhattan, Kansas and Pizza Today’s resident dough expert.