Introduction: In class we discussed the two different leavening agents, chemical and biological. An example of a biological leavening agent is yeast. One example for a chemical leavening agent is baking powder. In this experiment we used a chemical leavening agent. For this project, we selected a biscuit recipe, substituted an ingredient in the recipe, and predicted the outcome of the substitution. Below is all the outlined steps of this biscuit scientific experiment.
Research Question: If we substitute eggs for buttermilk, will the biscuits density, fluffiness, and moisture change as much as the original recipe?
Hypothesis/Prediction: We predicted that if we substitute the eggs for buttermilk, then the biscuits will rise more than the control group and be more fluffy and flaky. Some differences I think we will notice between our control and experimental group are that the control group will be dense and the experimental group won’t be as dense as the control group.
Materials and Ingredients: ● ● ● ● ●
Bowls Measuring Cups Baking Pans Whisks Pastry Cutter
According to MomOnTimeout, these are the ingredients: ● ● ● ● ● ● ● ●
All Purpose Flour Sugar Salt Baking Powder (Chemical Leavening Agent) Cream of Tartar Cold Butter Eggs 2% Milk
RECIPE (in grams for each category)
Calories
Carbohydrates
Fat
Protein
1 ½ cups of all purpose flour
661
138
0
24
1 ½ tablespoon of sugar
73
19
0
0
⅙ tablespoon of salt
0
0
0
0
2 teaspoon baking powder
0
0
0
0
¼ teaspoon Cream of tartar
0
0
0
0
⅜ Cold butter
1018
0.1
115
1
¼ cup of buttermilk
110
0
1.25
3
½ cup of 2% milk
75
6.5
2.5
4
1/2 egg
36
0.18
2.375
3.19
Total
1973
163.78
121.125
35.19
Procedure: The original recipe served as our control group, while substituting eggs for buttermilk created our experimental group. We didn’t want to bake two full batches of biscuits, so we adjusted each of the recipes by using the conversion factor of ½ . This chart below shows our data for the conversion factor.
Original Recipe
Control Group Recipe
Experimental Group Recipe
3 cups of All Purpose Flour
1 ½ cups of All Purpose Flour
1 ½ cups of All Purpose Flour
3 tablespoon of Sugar
1 ½ tablespoon of Sugar
1 ½ tablespoon of sugar
½ tablespoon of Salt
⅙ tablespoon of Salt
⅙ tablespoon of salt
4 teaspoon Baking Powder
2 teaspoon Baking Powder
2 teaspoon baking powder
½ teaspoon of Cream of Tartar
¼ teaspoon Cream of Tartar
¼ teaspoon Cream of Tartar
¾ Cold Butter
⅜ Cold Butter
⅜ Cold butter
1 Egg
½ of Egg
¼ cup of buttermilk
1 cup of 2% Milk
½ cup of 2% Milk
½ cup of 2% milk
According to MomOnTimeout, 1. Preheat oven to 450 degrees. 2. Combine the dry ingredients in a large bowl. 3. Cutting the butter into small pieces and incorporate into the dough. 4. Use a pastry cutter to cut cold butter into flour mixture. 5. Add in the milk and egg and mix just until the ingredients are combined. 6. Turn the dough out onto a floured surface and knead 10-15 times. 7. Pat the dough out to 3/4 - 1 inch thickness and cut with a biscuit cutter or glass. 8. Place the biscuits on a lightly greased baking sheet or parchment lined baking sheet and bake for 10 to 15 minutes or until golden brown on top.
The independent variable is buttermilk. The dependent variables (there are two!) is the leavening (measured by height of biscuits) and the texture (measured by my taste test). All my dependent variables are recorded in the table in the next section.
Baking: 1. Preheated the oven to 450 degrees. 2. We gathered our ingredients for the recipe. 3. Cut the butter into small pieces so it would be easier to mix into the dough. 4. Mixed all purpose flour, sugar, salt, baking powder, cream of tartar, cold butter together in two different bowls for the control and experimental groups. 5. We mixed the egg in the bowl for the control group and 2% milk in the bowl for the experimental group. We mixed the ingredients together for 5 minutes. 6. We patted out each dough on a flat surface by using flour and kneaded each dough 15 times. When the dough was sticky, we just sprinkled additional flour onto the dough. 7. Cut out the dough using a pastry cutter. We had 21 biscuits in total, 8 for the experimental group and 13 for the control group. The lesser amount for the experimental group didn’t affect the results of this experiment. 8. Next we placed the biscuits on a vegetable oil greased pan and separated the control group from the experimental by using flour. 9. We placed the biscuits in the oven. 10. We let the biscuits bake until they turned golden brown on top. 11. Finally, we let the biscuits cool, took pictures of them and tasted them.
Results and Observations: Dependent Variables
Control Group
Experimental Group
Rise height before baking
¼ inch
1/2 inch (2/4 inch)
Rise height after baking
¾ inch
1 ½ inch
Texture before baking
Dense
Moist
Texture after baking
Dense
Fluffy
Color before baking
Yellowish
Light Yellowish
Color after baking
Golden Brown
Light Golden
Taste after baking
Dry and Bland
Buttery and Moist
Other observation
Biscuits were flat and dense
Biscuits were thick, flakey and fluffy
Analysis: Our first observation that occurred before baking was that we needed to pat out the dough using flour. The dough was wet and sticky but a third cup of flour to each dough helped with that. Before we cut out the biscuits and put them on the baking sheet. Before baking, we measured the height of the biscuits for both groups. For the control group the biscuits height was ¼ of an inch and the experimental group of biscuits height was ½ of an inch. After baking for 10 minutes, they looked very white instead for golden brown. After the full 15 minutes, they had a nice golden color. We took the biscuits out the oven and cooled them for a few minutes. Next we measured the heights for both groups to see which group’s height rose more. The control group of biscuits were 1 inch tall. The experimental group of biscuits were 1 ½ inch tall. We pushed on the top of both groups of biscuits to see if they were fluffy at all. The experimental group of biscuits were fluffy but the control group of biscuits were dense.
Here are some Before and After Pictures of the Biscuits (Before)
(Control Group as Dough)
(Experimental Group, left and Control Group, right)
(After)
(Control Group Biscuits)
(Experimental Group Biscuits) Conclusion: My data show that I proved our hypothesis was correct: Buttermilk would make biscuits rise more and would affect the texture of the biscuits. Buttermilk made the biscuits become flakey and fluffy. Buttermilk in baking helps as a leavening agent. Buttermilk brings a pleasant tang to cakes, breads, biscuits and other baked foods while adding very little fat. It’s an acidic ingredient that helps tenderize gluten, giving baked goods a softer texture and more body, and it helps quick breads rise. Even though there was a leavening agent already inside of the experimental group recipe, adding buttermilk did help the biscuits rise higher and faster. My Final Conclusion: Buttermilk biscuits taste better than original biscuit recipes with eggs.