chocolate cupcakes

[martygreene]

I'm wondering if there is a baking chemistry reason that all the chocolate cupcake recipes I come across have vinegar in them and applesauce? I really liked the texture that I got in the rosewater cupcakes I made (and posted about here), and I'm wondering if I can modify that recipe so as to make chocolate cupcakes with it? Really- I don't have vinegar or applesauce, and still want chocolate cupcakes.

I know that baking is primarily chemistry, and so there might be some chemistry reason for needing the vinegar. If so, I can suck it up and get some another day and just postpone the cupcake making.