What determines how well cheese melts

Question

I have had my fair share of eating cheese and experimenting with them. Sometimes they come out heavenly while other times, it turn out to be a huge flop. Usually when it flops, it's because I am expecting the cheese to melt and it doesn't.

So my question is, what properties of cheese determines how well the cheese melts? This way I can determine in the future whether a cheese I am about to experiment with is meltable. Are there physical indicators that I can see and feel that can help me determine a cheese's meltability?

Is there a special way to increase how well cheese melts? I have noticed that some cheese melt slightly on the outside but the inside turn rubbery and doesn't melt.

Answer

Three factors influence how well cheese melts:

The amount of moisture,
The amount of fat,
How it was set.

The meltiest cheeses have a lot of moisture and fat and were set with rennet and not acid. Both moisture and fat leave space between the casein proteins that allows them to move. Otherwise they are packed together and don't flow as well.

Acid set cheeses don't melt much when heated dry because the acid denatures the casein in such a way as to cause it to bind more tightly.(although they will dissolve into hot liquids sometimes.)

This link is not authoritative but jives with my personal experience:
http://www.yumsugar.com/Burning-Question-Why-Do-Some-Cheeses-Melt-Better-Than-Others-2946119

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