Or is it the other way round? For instance when making a cheese cake.
Anyways, the more chemical the explanation, the better!
lemon-juice
Or is it the other way round? For instance when making a cheese cake.
Anyways, the more chemical the explanation, the better!
Best Answer
Lemon juice thickens condensed milk in the same way it would "thicken" regular milk, i.e., by curdling.
Basically, milk has two general types of proteins: casein and whey. The casein is what forms the "curds" in "curds and whey." Both proteins are somewhat unusual in that they don't tend to coagulate with heat (as eggs proteins do, for example). Thus, they will survive largely intact even with the processing of condensed milk.
Harold McGee in On Food and Cooking explains what happens when they encounter acids, though:
Thus, if you add lemon juice to regular milk, it will curdle and thicken, just as milk does when it sours naturally or when it is fermented into yogurt, kefir, cultured buttermilk, etc. (which all involve bacteria that acidify the milk). The same process happens if you add acid to condensed milk.