Where can I find egg white stabilizer? Not cream of tarter

Whisking in a copper bowl (copper on the inside) is a natural egg white stabilizer .

What are you using the egg whites for? I found rubbing the inside of the bowl I whip the whites in with the cut side of a lemon, then gently wiping out the bulk of the reside helped stabilize them. It's an acid, like cream of tartar, but doesn't add any off flavor, not that I ever noticed any from cream of tartar.