Ah, yes, the science of grilled cheese, a.k.a. goo-ology.
You guys, this is some serious business here! Grilled cheese is an art. It’s one thing to put some processed American cheese on some Wonder Bread and call it a day, it’s another thing to design a grilled cheese so delicious, so incredible, so perfect in every way that it makes your boyfriend look at you all wide-eyed and holler “THIS IS THE BEST GRILLED CHEESE I HAVE EVER HAD!” (I’m looking at you, Nate).
Before we get into the technique, we must understand and respect the cheese. As discussed in my previous blog post about homemade ricotta cheese, milk is primarily composed of two different proteins: caseins, which clump together during the cheese-making process while trapping fat molecules to form what we know as “cheese”, and whey proteins, which are strained out. Then, depending on the type of cheese, some are then aged to develop certain flavors and textures. So, knowing this, why do some cheeses melt and others don’t?
For starters, different types of cheese have different melting points, or the temperature at which a solid will begin to melt into a liquid, due to difference in water content. Cheeses that have been aged for a very long time, such as parmesan or romano, has very little water content as plenty of time has been given to allow the water molecules to evaporate, or turn from liquid to vapor. Cheeses that have been aged for a moderate amount of time, like cheddar or gouda, will require more heat to achieve melting, but still contain enough water content to do so. Ultra-creamy cheeses that haven’t been aged so much, such as brie and camembert, can melt just from the heat given off when holding it in your hand.
The actual melting of cheese occurs in two stages. First, the fat in the cheese melts from solid to liquid; this process actually doesn’t require a significant amount of heat and can happen even at room temperature for some cheeses such as brie. The second stage involves the caseins we talked about earlier. Caseins hold themselves together in little ball-like configurations in various types of chemical bonds. By increasing the heat, the atoms holding these chemical bonds together begin to increase in kinetic energy (or “movement energy”, as described in the blog post about barbecue sauce), and all this movement eventually causes the chemical interactions that are holding the caseins together to break apart. Since the structure of the caseins are what gives the cheese its structure, once they break apart, the structure of the cheese is, well, non-existent, which is what we observed as melted cheese.
Now that we’ve completed cheese melting 101, let’s talk about this technique. Sourdough bread gives structure and crunch to the sandwich while complementing the cheeses’ saltiness. A garlic-herb butter is used as heating these herbs directly on the pan will enhance their aromatics. The bread is buttered and cooked on both sides to achieve the perfect amount of butteriness and crunch, and to prevent the fat from the cheese from making the bread soggy. Upon flipping the bread to brown the other sides, shredded cheese is added in duos, such as smoked gouda and sharp cheddar or a 2:1 ratio of brie and gorgonzola, as the shredding will allow the cheese to melt consistently across the sandwich. Then, in a joining of loving matrimony, the two cheesy slices are laid down together and allowed to melt a little longer. And at last, we feast!
And now you know the secrets to the gooiest, crunchiest, most perfect grilled cheese. Enjoy responsibly.