What does the egg white do in peppermint creams?
Well, the sugar and lemon can act as stabilizers to the egg whites. It would help stiffen up the cream and allow it to be more spreadable. So to answer your question, the egg white is actually what's making the creamy texture, with the help of some other things. You could also substitute cream of tartar which is the acidic bi-product from wine making instead of the lemon.