Lab 36 – Baking Soda vs Baking Powder
This lab is conducted with grocery store items: Baking soda, Creme of tartar, Corn starch, and Baking powder. Additional products such as vinegar, and lemon juice can be used to illustrate reactions.
This lab is intended to illustrate the chemistry that occurs with cooking and baking – as well as a connection to body functions and chemistry.
Baking powder is a combination of baking soda, corn starch, and creme of tartar. These are a powdered base, a neutral moisture absorbing substance, and a powder base, respectively.
The reason baking powder is effective in baking is due to the reaction between the base and acid when combined in water. The reaction is visible if a small portion of baking powder is sprinkled into water. Gasious carbon dioxide is a bi-product of this chemical reaction in the form of small bubbles. This action helps baked products become “fluffy” during the baking process.
A nearly identifical reaction happens with a dry mixture of baking powder and creme of tartar. It will still occur with the addition of cornstarch. The combined ingredients are baking powder.
one part baking soda, one part corn starch, two parts creme of tartar
Baking Soda
Baking soda is sodium bicarbonate – or the bicarbonate of soda. Baking soda can be used as an antacid. Baking soda is a base.
NaHCO3
Several products use baking soda as an ingredient. Examples include toothpaste, antiperspirant, baby soaps, powder and shampoo, and in countless baked goods.
Creme of Tatar
Cream of Tartar is not creamy. It’s a dry, powdery, acidic byproduct of fermenting grapes into wine. Its chemical name is potassium bitartrate or potassium hydrogen tartrate.
KC4H5O6
Cream of Tartar is acidic. It is like lemon or vinegar. When cooking, for example, if a recipe calls for a teaspoon of cream of tartar, two teaspoons of vinegar or lemon juice can be used as a substitute. (Note, white vinegar would be recommended because it has less distinctive flavor).
Corn Starch
Corn starch comes from the starch part of a corn kernel. It is used as a thickener and has little if any nutritional value. Corn starch is 100% starch without any fiber, protein, fat or other components. Starch is a natural part of almost all plants. It is a common ingredient is foods such as in sauces (to thicken them), gluten-free fried coatings, puddings and custards, mixes for pancakes, some brewed beverages, and chewing gum.
C6H10O5
Baking Powder
Baking powder is a combination of baking soda and a powdered acid (e.g., crème of tartar). Baking powder often includes corn starch to absorb water so that the base and acid don’t react while in storage. When used in baking, water “activates” the reaction between the acid and base powders – making tiny bubbles of carbon dioxide (CO2).
(5:34) How to make baking powder – so easy