Buttermilk and Eggs
Here's one for you food scientists. The other day I was making a puffed pancake recipe that calls for whole milk, egg, flour and some flavourings (lemon peel and vanilla). You put it in a skillet and pop it in the oven for 10 or 15 mins. It puffs up real nice then you fill it with fruit etc. This time when I made the pancake I had no whole milk and thought I would add buttermilk instead. Well, the thing never puffed up. So my guess is the acid in the buttermilk interfered with what the egg does to puff the thing up. Does anyone have a better more detailed explanation?
Okay, one more time. Buttermilk is an acid. You needed to add some baking soda to counteract the acid and allow it to rise. For example if you are making biscuits or cornbread depending on quantity. Most recipes will call for some baking powder but when you add buttermilk to the equation it negates for the most the rising action of the baking powder and soda, usually about 1/2 tsp. needs to be added. It has nothing to do with your eggs. If you are whipping your egg whites to a meringue to fold in you might try to stablize them with a bit of cream of tartar but it is usually fat that makes egg whites deflate.
I don't think that's it. Puff pancakes depend solely on steam-rising (think popovers, not quick breads), so the lack of baking soda wouldn't have anything to do with it not rising.
I doubt that the acidity of the buttermilk was the problem either (although I do think it would have made a very strange-tasting pancake!) -- I'd bet that the buttermilk was just too thick and made the batter too heavy to rise. Was the batter thicker than normal? Usually those puff pancake batters are very thin, about the consistency of heavy cream. Steam-rising is a much more delicate process than yeast or chemical leavening, and when it doesn't work, it just flops completely.
I don't know the whys either, but I can say from experience that buttermilk makes great pancakes (traditional), but terrible waffles. My waffles have beaten egg whites and will be crisp outside but light and fluffy inside if I use skim milk. Buttermilk will make them flat and dense. Perhaps I'll try the extra baking soda.
OK, MichaelB I think you have the idea. I should have mentioned this was more like a souffle. The batter was the same consistency as before, as you said, like heavy cream. I have never had this recipe fail before and never used anything but whole milk in it. So the only time it didn't work was when I put in buttermilk. The next time I made it, I went back to whole milk and no problem. In any case, everyone thanks for your explanations.