Scrumptious Science: How Much Baking Powder Does Cornbread Need?
Have you ever wondered about the purpose of each of the ingredients in your favorite recipes? For example, why is baking powder used in some muffin recipes? How does the baking powder affect how the muffins look, feel and taste? In this science activity, you will use a scientific method to make some cornbread muffins to find out. And then you can decide on the best recipe to use if you want to make some cornbread for New Year’s Day, which is part of a Southern tradition where the cornbread symbolizes gold.
This activity is not appropriate for use as a science fair project. Good science fair projects have a stronger focus on controlling variables, taking accurate measurements, and analyzing data. To find a science fair project that is just right for you, browse our library of over 1,200 Science Fair Project Ideas or use the Topic Selection Wizard to get a personalized project recommendation.
If you examine the texture of a muffin or slice of bread, you’ll see that the basic structure is a random sort of meshwork that surrounds air spaces. Without the air spaces, the end result would more closely resemble a brick than bread. The air spaces are due to bubbles of gas (mostly carbon dioxide) produced within the batter during the baking process. Ingredients that produce these bubbles are called leavening agents.
In “quick breads,” which have no yeast (and don’t require hours for dough to rise), the leavening agent is usually baking powder. Baking powder is typically a mixture containing corn starch (to keep ingredients dry), sodium bicarbonate (a base, also known as baking soda), sodium aluminum sulfate (an acid) and monocalcium phosphate (another acid). When baking powder dissolves in liquid ingredients, the sodium bicarbonate reacts with the sodium aluminum sulfate and monocalcium phosphate. A product of this chemical reaction is carbon dioxide gas, the leavening for the baked product. As the batter bakes, the carbon dioxide produced by the baking powder makes bubbles in the batter. The bubbles are trapped by the surrounding structure of the batter, mainly supported by proteins in the flour and eggs.
Extra: Try repeating this activity but use different amounts of baking powder. For example, you could try half of a teaspoon or three teaspoons. How does using other amounts of baking powder affect how the muffins turn out?
Extra: If you have a kitchen scale, you could measure the weight of each muffin, and even calculate their densities. How do the weights of the muffins compare to each other? What about their densities? Do your results make sense to you?
Extra: Pick a different ingredient from the muffin recipe. Do research to understand the function of the ingredient in the recipe, and then predict what will happen when you change the proportion of that ingredient in the recipe. Can you accurately predict how changing the amount of a different ingredient changes how the muffins turn out?
Observations and Results
Did the muffins baked without baking powder turn out shorter and harder than the muffins from the other batches? Were the muffins made with one or two teaspoons of baking powder much more similar to each other?
Baking powder is a leavening agent that produces carbon dioxide gas during the baking process. The carbon dioxide gas bubbles become trapped in the batter as it bakes, forming air spaces in the resultant muffins. This is why the muffins baked without baking powder should have had many fewer air spaces, which made them flatter and denser than the other muffins. These muffins may have tasted and felt more like bread than fluffy corn muffins. The muffins baked with one teaspoon of baking powder should have seemed like typical corn muffins – they should have been somewhat fluffy with many air spaces. The muffins baked with two teaspoons of baking powder may have seemed very similar to the muffins with one teaspoon of baking powder, indicating that additional baking powder did not make a huge difference in how the muffins turned out. That said, the muffins baked with two teaspoons of baking powder may have seemed slightly fluffier than the ones baked with one teaspoon of baking powder, but overall these muffins should have been much more similar to each other than the ones made with no baking powder.
More to Explore
Teisha Rowland, PhD, Science Buddies
Science Buddies |
Baking, breads, recipes
Explore Our Science Videos
Fire Snake Experiment
Build an Infinity Mirror
Gel Electrophoresis and Forensic Science: Biotechnology Science Fair Project