Clarified butter: what happens if the foam isn't skimmed off? I know that most recipes for making clarified butter discard this foam. But I've also seen some recipes, like this one for ghee, which do not skim the foam.


  The butter will form a foam which will disappear. Ghee is done when a second foam forms on top of butter


Instead, the butter is left to simmer until the foam goes away. In my experience this happens around the same time the solids in the bottom begin to brown, which I'm guessing coincides with most of the water having boiled off.

Apparently, this foam is whey protein. Where does this protein go and what happens to it when the foam subsides after extended simmering? I've heard it suggested that it makes the resulting clarified butter grainy. Is that true?
The recipe you linked says that you have to strain the ghee. The solids will be left behind in the cloth. Ghee is a bit more cooked than other forms of clarified butter, I'm not sure if you could use this method without browning the milk solids.