The best cheese for grilled cheese sandwiches, according to science

It’s a quest that could last a lifetime — finding the perfect cheese for a grilled cheese sandwich.

We know that grilled sandwich, with its crispy, buttery bread, is the ideal vehicle for melted cheese. But the question that plagues us isn’t which bread to use — it’s what goes between the bread. You want something that will melt just so. Well, the scientists behind chemistry YouTube show Reactions have figured out what makes perfect grilled cheese sandwiches. Turns out what we need to pay attention to is a cheese’s pH.

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According to Reactions, the more lactic acid a cheese has, the lower its pH will be. Lactic acid is what contributes the “sharp” flavor to cheese, so a cheese with a low pH will taste super sharp. Unfortunately those cheeses don’t melt very well. They’re stucturally imbalanced, and the oil will separate from the rest of the cheese, leaving you with a greasy mess.

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What you want is something in the middle of the pH scale, usually between 5.3 and 5.5 (though there is one particular cheese with a pH of 5.8 that’s known for it’s melt-ability). The problem is that some higher-pH cheeses that melt well are mild in flavor. One way to make up for it? Try mixing some grated Parmesan into the butter that you spread on your bread before grilling it. You’ll get a nutty, crispy, umami bomb that’s the perfect vessel for a milder, melty cheese within.

Find out which cheese is the best for your next grilled cheese sandwich, according to science, in the video.

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