In questo articolo su Scientific American  la giornalista scientifica Meghan Bartels , ci spiega perché alcuni formaggi si sciolgono in una delizia filante, mentre altri semplicemente no.

Forget black holes or the origins of life—this is the sort of question that science was created to address.

Prateek Sharma, scienziato alimentare presso la Utah State University dice che è tutta colpa (o merito?) di una proteina, la caseina

In milk, casein delivers the vital nutrients calcium and phosphate to a calf, lamb or baby. But the cheese-making process turns casein into a network held together by weak bonds and studded with molecules of water and fat.

In general, the dissolution of that network—the melting of the cheese—plays out in stages as the cheese is heated, Sharma says. First, beginning as cool as around room temperature, the cheese’s assorted fats will begin to melt and seep out of the network, floating to the surface (this is why cheese gets sweaty). Next, as the cheese reaches the temperature of water from a hot tap, the proteins within it start losing water, shrinking and softening. By around 160 degrees Fahrenheit (circa 70° n.d.c.) the melting process is complete.

Ma qui comincia il bello

But thoroughly melted cheese doesn’t act like typical melted substances. When ice, butter and chocolate melt, they become liquid: they flow and drip. In contrast, mozzarella oozes and stretches, making it the poster cheese for good melting.

Sempre per merito della caseina

more specifically, as a function of the loose interactions between casein molecules. The casein network needs to be flexible enough to move but rigid enough that the cheese hangs together. Increasing the amount of water or fat locked into the casein network can encourage melting, but so can modifying the casein itself.

Secondo John Lucey, scienziato alimentare presso l’Università del Wisconsin-Madison e direttore del Wisconsin Center for Dairy Research è l’acidità il trucco che usano i produttori

 In cheese made at a relatively neutral pH, there are enough calcium bonds that casein molecules are stiffly bound to each other. Add some acid, and things start to loosen up in the resulting cheese

Infine

All this emphasis on the role casein plays in how cheese melts also helps to explain why vegan cheese—with no casein at all—is relatively soft even when chilled and often downright unappetizing when heated

Neil Cunningham, uno scienziato presso il Center for Industrial Rheology in Inghilterra afferma che

“Plant-based cheeses, they start off as cold Jell-O, and then they become hot Jell-O”