So, we know that the early history of chemical leavening was defined by a search for non-poisonous gas-producing alkalines to combine with non-poisonous acids to produce bubbles. It wasn’t easy. There are hardly any edible alkalines in our collective pantry to begin with. In fact these days there are only two: egg whites and baking soda, soda being the only one of any strength. So, on the alkaline side of the leavening equation we have soda. And on the acid side? Well, let me see, in the typical baker’s pantry we have:
Cream of Tartar
Any of them can be used, in just about any combination, to react with baking soda and create leavening. It all depends on how much acid you need to push up your cake, cookie, bread or biscuit. Interesting isn’t it? I’ll make food chemistry geeks out of you people yet.
(NOTE: This list has nothing to do with the pseudo-science of Nutripathy, which holds that foods are either acid or alkaline “forming” depending on the effect they have on the pH of one’s urine or saliva. I don’t mess with the kooky stuff, man.)