The (delicious) science behind baking pizza cheese
Piping hot, fresh out of the oven, brimming with a generous portion of cheese and your favourite toppings. Baked to perfection, leaving you with a warm, chewy crust, and a delicious, gooey centre. As cheesy as it sounds (Yes, it’s a terrible, unintentional pun), I’m referring to a beloved food that has captured millions of hearts worldwide: pizza.
Pizza has become a worldwide treat for decades that global regions even adopt their own local variations. Styles of pizza ranging from deep dish crust, shrimp, saltwater crocodile, caviar, and even potatoes, reflect the unique tastebuds of various regions from around the globe. Whatever toppings we choose to throw on top of our pie, most people can agree that cheese is vital for any delicious pizza.
Recently, researchers conducted a study to investigate the traits of different pizza cheeses during the pizza baking process. Several pizzas were prepared using either mozzarella, cheddar, colby, edam, emmental, gruyere, and provolone cheese. After baking in the oven, all pizzas were photographed to compare the browning of each cheese, which were then quantitatively compared. The objective of this study was to investigate the different traits of various pizza cheeses during the cooking process.
All cheeses and pizza bases were purchased at a local delicatessen in Auckland, New Zealand. Researchers ensured that each pizza was ‘equal’ in preparation, ensuring uniform cheese distribution and even cooking times (5 minutes at 232°C). Each pie was quickly photographed in a light box system, and their colour traits (‘even colour distribution’, frequency of cheese browning/blistering) were analyzed using computer software and mathematics.
All pies are not created equally
The researchers observed that cheese colour and the frequency of ‘brown spots’ (bubbles where the cheese has blistered and burned) is primarily dependent on the cheeses’ internal water activity, which influences its capability to change temperature upon exposure to the oven heat. Ma et al. (2014) observed that cheeses with high water activity undergo minor changes in temperature (upon baking). As a result, these types of cheeses will melt easier than others, producing a pizza with evenly distributed cheese, complete with very little cheese blisters/burns. Cheeses such as colby and edam produced a uniform cheese colour on its pizza with very little browning. The study reported that mozzarella had the highest water activity, even though it produced many cheese blisters. The researchers argue that a cheese like mozzarella will possess unique traits (i.e. aging) that will allow them to do behave stochastically.
Additionally, the study also observed that a cheese’s moisture content, free oil content, and elasticity contribute to its characteristic qualities upon baking. Ma et al. (2014) argue that said factors determine whether or not cheese blisters will form on the pizza. Cheeses such as cheddar, edam, and colby, were not able to produce cheese bubbles due to its poor elasticity responses, unable to resist uprising steam (related to moisture content). As a result, the cheese bubbles were ‘popped’ before they could even form into the brown blisters. Furthermore, cheeses such as gruyere and provolone were not efficient at producing cheese bubbles, due to their high free oil content, which ‘lubricates’ the forming bubbles, preventing burning.
Ultimately, out of the all the cheeses in the study, mozzarella was able to produce a pie with non-uniform colour and copious cheese bubbles. Mozzarella’s unique traits, along with its high moisture, low free oil content, and high elasticity, allow the cheese to achieve the look and taste of pizza that we all know and love.
So, uh, what was the point of this study…?
Sure, some of us can argue that this study may not hold a lot of merit for a biomedical researcher, microbiologist, or a physicist. Some may even have the audacity to argue that these kinds of research studies don’t actually have any practical, useful applications at the moment, and may only hold some use to pizza makers, food scientists, and culinary aficianados alike. But I prefer to think otherwise. I believe this study and many other like it can contribute some use to various projects today. Perhaps (real) vegan cheese makers and/or engineers designing the 3D pizza printer for NASA can benefit from the results of this research. Additionally, maybe these results can allow us to design “attractive pizzas”, which may or may not influence our perception of its taste.
If you don’t agree with me though, I hope this article made you hungry anyway. Now go get a pizza.
Renee C. has received her B.Sc. in Honours Life Sciences at McMaster University. She loves educating others about different topics in science, and has developed a passion for scientific outreach. When she’s not writing articles for Hemtecks, she’s either volunteering or checking her social media accounts every 20 minutes. Along with Tiffany (Tianhemtecks), she also facilitates the blog’s Facebook page.