http://www.straightdope.com/mailbag/mbakingsoda.html
I’m not sure what cookbooks our intrepid mailbag person is looking in, but practically every muffin or pancake recipe I’ve ever seen calls for both baking soda and baking powder. This would seem to suggest that they have different purposes. Anyone know?
Nope, Hawk nailed this one. The reason so many recepies call for both baking powder and baking soda is they have a certain ammount of acid calling for the baking soda, but not enough to create enough rise, therefore also calling for baking powder. I would like to note, Hawk claims buttermilk and yogurt as most common recipe acids, while I would think lemon juice would hold that lofty title. Of course, that’s just my opinion. BTW if you see a recipe calling for baking powder, baking soda, and cream of tartar, that’s just the recipe’s creator being goofy.
Okay, that makes sense in terms of muffins and quick breads that need a lot of rise in a heavy dough without yeast, but why would both be needed in pancakes? (The recipe I’m thinking of is for buttermilk pancakes, BTW.) Maybe the recipe’s creator just added both because he/she was used to adding both to other recipes.
I made bananna nut bread yesterday, and the receipe calls for baking soda, baking powder, and salt. My favorite muffin receipe calls for both as well.
Well cher, since they are buttermilk pancakes you could try removing the baking powder, but I would think they would be a little flat 
I imagine you need quite a bit of rise in pancakes since they cook so quickly.
I have a recipe from my Joy of cooking that calls for 1 1/4 tsp baking powder, 1/4 tsp baking soda and 1 1/4 cups buttermilk. Keeping in mind baking powder is one part baking soda and two parts cream of tartar that’s 5/12 tsp baking soda (close enough to 1/2) and 5/6 tsp cream of tartar (close enough to 1) that means 1 1/4 cups of buttermilk has the same acid as about 1/2 tsp cream of tartar. In this recipe you would need to increase the buttermilk to 3 3/4 cups and the baking soda to 3/4 tsp to get the same ammount of rise which would make a rather thin batter, or increase the baking powder to 2 tsp and just deal with a slightly sour batter. It just comes down to what acids you’ve got in the ingredients.
I can’t dispute anything Hawk has said about baking powder, but the baking soda story must be inclomplete. I’ll cite two cases:
[ul]Chocolate Chip (Toll House) cookies. Every recipe I’ve seen for these, including the one on the Nestle’s package, calls for baking soda only, but not a reactive acid. Flour, sugar, bro2wn sugar, eggs, water. So where do the bubbles come from?
Peanut brittle. The good peanut brittle, the kind that breaks up satisfyingly when you bite it, has jillions of tiny air (okay, CO2) bubbles all thorugh it. This is done by sprinkling in a 1/2 teaspoon or so of baking soda right before you remove the stuff from the heat. Only ingredients are sugar, water, corn syrup, peanuts.[/ul]
On NPR’s radio show “Rewind” yesterday they had a question about “baking ammonia” which some cooks tout as a superior leavening agent. IIRC, it is made of ammonium bicarbonate and supposedly creates lighter, fluffier baked goods. It doesn’t age but it can evaporate(!) if left open. There is an ammonia vapor odor while baking but it doesn’t affect the flavor.
They had a website where you could order it, which, of course, I’ve forgotten, but it was like $3.95 for a tin of it.
“Cheddar?”
“We don’t get much call for that around here, Sir.”
The following is from “Cookwise” by Shirley Corriher, who knows just about everything about food science: some recipes call for both baking soda and baking powder. this may seem redundant… but there are good reasons to use both. Baking powder is very reliable since it has just the right amount of acid for the amount of baking soda. But sometimes a recipe also contains aan acidic ingredient, and adding a little soda will neutralize the extra acidity."
Common acidic ingredients in baking are buttermilk, yogurt, sour cream (pretty obvious) and also brown sugar, honey and molasses (not so obvious).
Hey Matt, as noted above by Janet Brown sugar is acidic, so that should answer your toll house question. Interestingly enough, my peanut brittle recipe calls for Cream of tartar but no baking soda, go figure.
Wow, 13 minutes to get an answer - and the added bonus of learning about the pH of sugar.
But I gotta believe that there’s another factor at work. Baking soda will release CO2 when exposed to acid. But mix up water, sugar and baking soda, and you won’t see any bubbles.
Add baking soda to boiling hot (maybe 250F) sugar water and the bubbling is furious. Does the heat just speed up the reaction with sugar, or would the CO2 be released anyway if the acid of the sugar was neutralized beforehand?
(btw can I make sub- and super-scripts with UBB?)
This may be a bit nit-picky, but milk is acidic (see: http://www.miamisci.org/ph/hhoh.html ). So considering that it is 6.6 and baking soda is 8.3, a good amount of milk should neutralize a small amount of baking soda.
AskNott
"Measure twice, cut once. Dang! Measure again, cut again.