Your gut and taste buds have probably already informed you that melted mozzarella on pizza rules. But do you know why mozzarella is so perfect for pizza?

Researchers at the University of Auckland recently published a paper in the Journal of Food Science titled “Quantification of Pizza Baking Properties of Different Cheeses, and Their Correlation with Cheese Functionality.” The paper explored what makes mozzarella the ideal pizza cheese.

The answer lies in mozzarella’s unique browning and blistering patterns, of course. Just look at the image above. Your eyes instantly flow toward the mozzarella-topped pizza on the left.

Dr. Bryony James and her team covered pizzas with a specific depth of each type of cheese, then baked each pizza in the oven for a specific time.

The scientists didn’t trust their eyes alone. Instead, they took photos, and then used special computer software to quantify the color uniformity of the cheeses, according to the BBC.

But they didn’t stop there. Each cheese’s stretchiness, moisture content, oil content and release during melting, and temperature of melting were also taken into account.

pizza cheese

To brown nicely, the moisture content of cheese must come to a boil and create steam as it cooks. If the cheese is elastic enough, a bubble forms. Large bubbles result from more elastic cheeses. As the steam makes cheese bubble, oil from the cheese begins to gather on top of the pizza. The larger the bubble that forms, the more easily it can break the surface underneath the oil slick—using the combined powers of oiliness, elasticity, and steam to brown the surface of the cheese.

Cheddar, colby, and edam failed because they’re not very elastic. Gruyere and provolone were too oily, so good browning couldn’t happen. Emmental wasn’t moist enough.

Dr. James and her team found that mozzarella alone combines these elements in the most pleasing way to human eyes (and palates).

One important thing to note about this experiment: the researchers didn’t use any sauce on any of the test pizzas.

The reason? Dr. James and her team wanted to limit the number of variables involved.

While no one can ever seem to agree on which pizza toppings are appropriate—and which are total abominations in the sight of the Pizza Gods—we have to ask: who eats pizza without sauce? (Unless we’re specifically talking about white pie, of course.)

pizza sauce

Dr. James even talks about how every pizza ingredient plays a role in how cheese melts. In the video below, she said

It is dictated by a combination of the composition and the mechanical properties of the cheese itself, as well as every other component of the pizza.”

In our opinion, the lack of sauce makes the research a little half-assed, but not non-credible. We’re looking forward to additional scientific experimentation and explanation in the field of pizza—but hopefully with better real-world applications for our lunch.

For a full rundown of all the details of this experiment, Dr. James posted this video on YouTube.

[via the BBC, YouTube]

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