Ellen Phiddian
Cosmos science journalist
What’s pizza dough without yeast? Apparently it can still be fluffy and tasty, as long as you use the right fluid dynamics.
A team of Italian scientists have figured out how to make yeast-free leavened pizza dough using just flour, salt, water – and an autoclave.
Publishing their results in Physics of Fluids, they say that their dough method will be helpful for the growing number of people with yeast intolerances. Unusually for the subject of a scientific paper, this dough is edible straight away, and the researchers say it tastes pretty good.
The researchers developed their dough with the help of a specially-purchased hot autoclave, a machine designed to increase temperature and pressure.
More on yeast: Zeitgeist: Rising in the yeast
The autoclave could dissolve gas into a small ball of dough at high pressure, which then forms bubbles during baking, just like yeast. The process is very similar to carbonating drinks – gases are added at a high pressure, and they then expand when the pressure is released.
But unlike opening a bottle of mineral water, the researchers had to be much more careful with releasing pressure on their dough.
“The key to the process is to design the pressure release rate not to stress the dough, which likes to expand gently,” says co-author Ernesto Di Maio, a professor at the University of Naples Federico II, Italy, and possessor of a yeast allergy.
The researchers then used traditional methods to make a control yeast-dough, monitoring its baking and temperature in a wood-fired oven helpfully provided by a local pizza joint.
They then used a number of instruments to examine the rheology of the pizza dough: its deformation, and the flow of gas bubbles inside it.
“We mainly studied how dough behaves with and without yeast: how the softness changes with leavening, and how the dough responds to a temperature program during baking,” says co-author Rossana Pasquino.
“This was fundamental to designing the pressure protocol for the dough without yeast.”
The method should work for other yeast-based doughs as well, like breads and cakes.
While they’ve enjoyed sampling their results, the researchers (who also count a professional pizza maker among them) are now keen to scale up their results. They’ve purchased a bigger, food-grade autoclave, and will be investigating making full-sized pizza bases, ultimately hoping to see their method appear in pizza shops.
“We had a lot of fun applying things we know well to delicious polymers, instead of our typical and sometimes boring smelly plastics,” says Pasquino.
“The idea of approaching food samples with the same technologies and knowledge used for thermoplastic polymers was surprisingly successful!”