Pizza at Pastamadre, part #1: It's all about crust
Undoubtedly pizza making is an exciting adventure that if it ends up successfully gives great pleasure to the pizza maker and of course to everyone that eats it. The successful outcome similarly with most cooking activities depends on two factors, passion and knowledge. In case of pizza you need to add also patience. I take passion and patience for granted and I focus here on the knowledge. Pizza, like other fermentation processes, does not rely on precise recipes. Following a pizza recipe without adequate knowledge of the ingredients and the underlying principles will lead either directly to fail or at best to short and rather accidental success. We assemble a dough made of flour and water that will run a life circle before it dies to a perfectly baked crust. During this journey they take place incredible chemical and physical transformations and the more we know about them the better the chances to succeed.
But, what define s success, what means exactly a good pizza crust? Even though there are different preferences, also in Italy, the motherland of this food, we can somehow find a consensus and ask for a good crust to have:
1) a lightly crispy exterior and an airy, moist and chewy interior, that allows us to easily fold each piece. By no way too crispy and dry that brakes into pieces like a biscuit and also not compact and stiff with a heavy catch in the hand.
2) a pleasant after feeling with no particular sensations of heaviness and stomach disturbance.
Here, I discuss two topics that influence greatly crust properties using as an excuse two common notions that people have about pizza which are not necessarily correct.
Notion 1: For a good pizza crust you have to use a flour named double zero (00) that is commonly used by the pizzaioli in Italy.
Notion 2: It is not possible to get a pizza at home as nice as the one you eat in a good pizzeria.
Pizza is made of flour, water, salt and a leavening agent, which can be either a sourdough culture (that is again flour and water) or baking yeast. Water and salt are affecting the outcome in several ways but in principle are just water and salt; no need for special types of them. But flour is a more complex matter because simply it exists in many different types, coming from different grain sources. By no means I use flours designated as pizza or all-purpose flours. Even though they could give a good pizza in combination with proper handling by the pizza maker, I still want to know their origin, what makes them to be named pizza flours and then judge by myself if I want them or not. So, what flour then is proper for pizza? A simple answer is a strong flour, that is a flour with a good amount, but also a proper type/ratio of two proteins (gliadin and glutenin) that in presence of water they form the gluten network. A well-formed and strong gluten network will keep the gases produced by the yeasts in the dough and thus will give rise to a light and airy final crust. In this regard, wheat flours are commonly used for pizza since they contain the required blend of gliadins and glutenins.
But not all wheat flours are necessarily strong flours since the exact protein composition is affected by environmental and growing conditions, but also by the processing during production. In that sense there are strong but also weak wheat flours and unfortunately in most cases the strength of each is not even indicated on the packages we buy. The only information that is usually written its the nutrient composition and among others the total amount of proteins that even though it is not an accurate proxy for the flour strength it can be still used as a good estimate. Based on this, for a strong flour we are looking for a total protein content of at least 11.5-12%.
The flour quest can be though more complex since wheat flour exists in several types that in every country have different letters or numbers. This is due to the gradual processing of the wheat fruit (wheat kernel) via grinding as to transform it to flour. The grinding operation is followed by several sieving steps to separate the soft, white, internal material (endosperm) of the wheat kernel from the external hard parts, namely the bran and the wheat germ.
The different numbers/letters on flour packages indicate somehow the bran/germ content of the flour. Indirectly they indicate also the nutritional value of the flour, since more of the bran and germ the flour contains, less refined it is and richer in an array of minerals and vitamins. These nutrients are found mostly in the bran and germ, while the soft endosperm contains mostly carbohydrates (starch) and the proteins, mainly the gliadins and glutenins, but also others. Italian flours have numbers like 00, 0, 1, 2 while German flours have numbers like 405, 550, 1050 respectively. In both cases, higher the flour number more of the bran and germ it contains or in other words more nutritious it is.
In principle all those flours can be used for a pizza dough providing that the protein content is adequate. We just have to keep in mind that a high-number flour will produce a more nutritious food with pronounced character and taste but at the same time the gluten formation will be compromised due to the bran particles that work like small blades and rip locally the gluten net. This becomes usually evident only when we try to assemble a dough using whole wheat flour (vollkorn weizenmehl) that contains the whole bran and germ. But even in this case a good gluten network can be still formed with some ‘advanced’ kneading skills from the pizza maker. To conclude, which one or which flour combination we will finally use depends solely on us and of what we are aiming to get. We want an easy to work dough that will produce a rather plain, white crust with an airy and light interior but diminished nutritional value? For this we use a low-number flour. We want a crust with more character, taste and higher nutritional value? We simply go to higher numbers but we are ready to knead and work the dough a bit more.
To make our quest even more complex but also interesting, we can consider using additional flours coming from other wheat varieties. Except of normal/soft wheat (weizen), we could use also hard/durum wheat (hartweizen), dinkel, kamut etc. From the above, durum has a high amount of gliadins and glutenins and gives rise to good gluten structures. Moreover has a particularly ‘rustic’ taste and is usually among my favorites for bread making. Due to its harder nature, durum is being processed differently than soft wheat and exists mainly as an endosperm-rich flour which has a sand-like appearance and is named durum wheat semola or semolina (hartweizengrieß). This is the product that Italians use to make pasta but could be used equally well for breads and pizzas (1).
How and where we bake the pizza is very important and it will define substantially the texture and consistency of the final crust. Indeed, pizza needs to be baked in a hell-like environment. Higher the oven temperature, shorter the baking time. This translates to less water loss due to evaporation and thus softer and more delicate crust. Take for example the classical pizza Napoletana. It is baked in wood-fired ovens that raise the floor temperature up to 485°C. In these conditions, the pizza will take between 60-90 seconds to be baked and will be soft, velvety, easy foldable, lacking even any crispiness. At home, in a conventional oven that raises the temperature to 220-250°C, the pizza will take approximately 10 min to be baked and will loose substantially more water, hence risking to give a rather dry and semi-hard crust (a common result for home pizzas).
Can we somehow overcome this issue and get a soft and tender pizza at home? Of course or at least up to an extend. Simply, we need to add more water in the pizza dough, in other words to increase dough hydration (percentage of water related to flour). For instance, consider the recipe for the pizza Napoletana that asks for a dough hydration of 55-59%. If we try to bake this pizza in a conventional home oven we will end up with a crust completely dry and cracky. To avoid this we simply increase dough hydration, for instance up to 65-70% (2). But in this case and because the dough will be stickier and more challenging to handle, we need to devote more time kneading it as to develop adequate strength. Additionally, we need to be gentler opening the pizza disk, avoiding acrobatics and to use flour accordingly as to prevent sticking and braking.
As an alternative to conventional oven, they exist also small pizza ovens and pizza stones. These surfaces are raising high temperatures (higher than 300°C) and thus can bake a pizza in shorter time than a conventional oven, usually between 3-5min. Some of them they are affordable and do not consume a lot of energy, thus can be accessories worth of purchasing. But still, even a conventional oven with proper handling can deliver a pizza that you can be proud of it!
(2) Each flour absorbs differently the water and the exact hydration level depends on the flour type. For instance, whole grain flours absorb more water that refined, white flours.