September 7, 2012 |

Tough Dough

By Tom Lehmann

There are a number of things that can cause a pizza crust to become excessively tough or chewy. The tough and chewy stage is set when a high protein (very strong) flour is used to make the dough. Pizza crusts made with a high-protein flour of 13 percent or more can have a wonderfully light and crispy eating characteristic when the pizza is fresh and hot out of the oven, but upon standing for much more than 10 minutes it can become tough. This can happen on a buffet serving line, or in a box and/or insulated bag while the pizza is being transported to a customer’s home. The development of toughness is a result of moisture migration from the hot, moist toppings into the dry, crispy crust portion of the pizza. This is the reason we have those neat “ripple sheets” that you can set the pizza on in the box. The idea here is to hold the pizza off of the bottom of the box, thus allowing channels for the moisture to escape from the bottom of the pizza. We have found over the years that pizzas made from a slightly lower protein flour (in the 12 percent protein content range works will be just as crispy as pizzas made with a higher protein flour, but they will not become as tough and chewy over time.

Another cause of a tough and chewy crust is the development of a gum line in the pizza. The pizza can be baked so it looks great, and it will even have a good crisp to it, but when you take a close look at the inside of the pizza you might see a gray line just below the sauce. This is a gum line. The gum line represents a portion of the crust that has not been fully baked. As a result it has a greater moisture content than the rest of the crumb portion of the crust. After baking, moisture quickly moves out of this gum line and into the lower moisture areas (think crispy areas) where it does its dastardly deed of creating toughness and chewiness. If this is the cause of your problem, you will need to take steps to correct the gum line. This can include baking a little longer at a slightly lower oven temperature, not pre-saucing the dough skins, not thinning the sauce quite so much (try to get your sauce to about 12 to 13 percent solids), or you might be able to correct things by just applying a very thin coating of oil to the surface of the dough skin before saucing it.

We use fresh, compressed yeast. Does it make any difference how we add the yeast to the dough?

Yes, it does. A common way to incorporate the yeast into pizza dough is to add it into the water containing the salt and sugar. This is not a recommended practice as it can lead to damaged yeast, resulting in inconsistent yeast performance. This happens as a result of the potentially higher osmotic pressure of the salt/sugar solution. What this means is that the salt and sugar, under certain circumstances, could pull moisture — including essential enzymes and amino acids — out of the live yeast calls. This can lead to soft dough conditions, as well as less-than-ideal fermentation characteristics. To avoid this, we simply recommend that the salt and sugar never be allowed to come into direct contact with each other, even when in a solution. This is recommended for all kinds of yeast, not just compressed yeast.

We see that a good number of operators are in the habit of putting the yeast into the water and stirring it until the yeast is “dissolved.” But, frankly, I’ve got better things to do with my time, so we can dispense with stirring the yeast in the water. Just crumble it a little and add it right on top of the flour and it will get mixed into the dough just fine. I promise.
With all of this said, there is one small exception that you do need to be aware of. When using a vertical cutter mixer (VCM), the dough mixing times are so short that it can be difficult to get the yeast thoroughly dispersed throughout the dough without a little help. This help comes in the form of adding the yeast as a suspension. Put the yeast into a bowl containing a portion of the dough water, then add the yeast. Next, use a hand whisk to stir the yeast until it is completely suspended, then add it right on top of the flour in the mixing bowl. This won’t be a problem if you happen to use active dry yeast (ADY) since it must be pre-hydrated in a small portion of warm water anyways. But if you are using instant dry yeast (IDY) you are going to have to pre-hydrate this one too. Do this by putting the IDY into about five times its weight of 95F water and stir using a wire whisk until the yeast is fully hydrated and suspended in the water, then pour it onto the flour in the mixing bowl. Be sure to reduce the amount of water added to the bowl by the same amount of 95F water used to hydrate the yeast so that your dough formula remains in balance.