Baking Soda Turns Batter Brown?
This has happened to me a couple of times when baking light-colored cakes and bread - although I couldn't definitively attribute the coloring to baking soda. However, I just read an article about making pretzels in the New York Times, and the dark brown coloring on the outside of pretzels can be created by dipping the pretzel in a alkaline solution (lye) before baking.
Can baking soda darken doughs and batters?
According to Shirley Corriher in Bakewise, baking soda is often used to turn cookies brown and larger amounts help, not with the rise, but with the color. The more alkalized a product, the darker. I tried to find a link to it but couldn't. You do boil pretzels in hot water w/ a base, often lye or baking soda for that brown color.
Here's a little more info about leavening in general in cookie recipes and baking soda's specific effect, from the American Institute of Baking:
"Leavening ingredients help to control spread or size, produces volume and promote proper crust color through regulation of acidity or alkalinity (pH) of the dough. Cookies that are hand dropped, deposited with a pastry tube, or machine deposited, need the spread control of leavening agents. An alkali such as baking soda exerts a weakening effect on the flour proteins (gluten) and helps to promote spreading. Since most cookie ingredients are neutral to slightly acid, they are usually sufficient to neutralize any reasonable quantity of baking soda added."
"Cream of Tartar, a baking acid is used with soda as a leavening agent. A fast acting baking powder can be made by combining two parts of cream of tartar with one part baking soda. When cream of tartar is used without a counteracting alkali such as baking soda, it increases the acidity of the dough or batter. The higher acidity produces a whiter crumb color and a lighter crust color because sugar carmelizes at a higher temperature in an acid media."
"Baking Powder is a mixed blend of food acids of which there are several types and Bicarbonate of Soda with starch added to prevent the Baking Powder from lumping during storage. During the baking process the acid ingredients and the baking soda contained in the baking powder are dissolved in the liquid forming carbon dioxide gas. None of the acid nor the the soda remain in the finished product, because they neutralize each other. "
"Bicarbonate of Soda- Bicarbonate of soda, an alkali salt can be added alone or as a component of baking powder. The alkalinity of baking soda lowers the carmelization point of sugar in the cookie dough or batter, causing faster and darker coloring of the crust. Soda also has a weakening effect on flour proteins. This action is more pronounced when soda is used without the counteracting food acid. Some of the alkalinity of the soda is neutralized by the natural acidity of the other ingredients in the formula. Too much soda will result in a chemical reaction between the fat in the formula and the soda. This will result in the cookie having a soapy taste."
Yes, they are different reactions. The short answer for this question is that they are both promoted by heat, but the Maillard reaction involves amino acids and sugars, where caramelization is simply the pyrolysis (chemical decomposition of substances, occuring spontaneously when heated to high temps) of certain sugars. The effect of both of these reactions can appear similar to the eye but different chemical reactions are taking place.