Baking Bread RP Partners: GA DM May 11, 2017 For this lab report we had to make three different loaves of bread, each with a different leavening agent. We made one with baking soda, one with yeast, and one with sourdough starter. Leavening agents are used because they help baked goods rise. When leavening agents are added to the dough, the leavening agent will eat the sugars from the flour and release CO2 which causes the dough to expand. Yeast takes longer to rise and is a biological leavening agent so that is why the yeast bread is our control group. The sourdough and the baking soda bread are the experimental groups because they are chemical leavening agents are do not take long to rise. My hypothesis was that the bread with the biological leavening agent, yeast, would release the most CO2 and so rise the most. However, the bread with the chemical leavening agent, baking soda, increased the most in volume when I compared the size before and after it went into the oven. Baking soda only works in the presence of an acid, pH less than 7, so we added buttermilk, which is not a base, but an acid. Apparently, baking soda releases more CO2 than yeast. The question for this experiment was which leavening agent would make the bread rise the most. Obviously there is no time to make all three of the breads, so my group made the baking soda bread. Ingredients​: Yeast Bread (Control Group) Ingredient
Calculations
Revised Amount
3 Cups Water
3 divided by 4 =
3/4 cups of water
6 1/2-7 1/2 Cups All-Purpose Flour
6 1/2 divided by 4 =
1 5/8 cups flour
1 Tablespoon Salt
1 divided by 4 =
1/4 Tablespoons of Salt
1 1/2 Tablespoons Yeast
1 1/2 divided by 4 =
3/8 Tablespoons of Yeast
Sourdough (Experimental Group 1) Ingredient
Calculations
Revised Amount
4 cups of water
4 divided by 4
1 cup
10 cups of all purpose flour
10 divided by 4
2 1/2 cups
¾ cups of sourdough starter
3 1/4 divided by 4
13/16 teaspoons
3 ½ teaspoons salt
¾ divided by 4
3/16 cups
Baking Soda Bread (Experimental Group 2) Ingredient
Calculations
Revised Amount
3 ½ cups flour
1* 3 ½ = 3 ½
3 ½ cups of flour
1 teaspoon of sugar
1*1=1
1 teaspoon of sugar
1 teaspoon of baking soda
1*1=1
1 teaspoon of baking soda
1 teaspoon of salt
1*1=1
1 teaspoon of salt
2*1 =2
2 cups of buttermilk
2 cups of buttermilk Procedures: Yeast Bread (Control Group) 1. Combine all of the ingredients in a bowl. 2. Mix everything until you get a sticky dough. 3. Let your dough rise at room temperature or in the fridge for 2 hours 4. Bake the dough at 450 F for 25-35 minutes or until golden brown. 5. Let the bread cool for 1-2 minutes. Sourdough (Experimental Group 1) 1. Mix all of the ingredients together. 2. Knead the dough for 10 minutes. 3. Let the dough rise for 4-6 hours at room temperature or 10 hours in the refrigerator. 4. Bake it for 40 minutes to 1 hour at 500 F.
5. Let the bread cool and eat. Baking Soda Bread (Experimental Group 2) 1. Mix all of your ingredients together in a bowl, except the buttermilk. 2. Add the buttermilk after all of the dry ingredients are mixed. 3. When you have your dough, do not knead the dough because it will become very heavy. 4. Place your dough on a baking sheet and cut an X in the middle so the air can escape. 5. Bake the bread at 450 F for the first 15 minutes, then at 400 F for 20-30 minutes for or until golden brown. 6. When it is done, stick a thermometer inside the bread and make sure it is 195 F to 200 F. Results This table summarizes what we observed from our controlled experiments. Observation Height
Control Group
Experimental Group 1
6.5” by 4” by 2” = 52 7” by 4” by 2”= 56 in^3 in^3 6.5” by 4” by 2.75” = 8” by 4.5” by 3” = 71.5 in^3 108 in^3 Percentage Change: Percentage 28% increase Change: 108% increase
Taste
It looked a little burnt around the crust and very soft and shiny in the center.
8” by 8” by 2.5” = 160 in^3 8” by 8” by 4” = 256 in^3 Percentage Change: 60% increase
Did not taste, but heard it was very salty.
It tasted awesome and flaky. I tasted a bit nutty.
It was very round, hard, and crunchy.
It looked a little burnt around the crust.
It tasted perfect. It was a perfect balance of everything Appearance (holes, airiness)
Experimental Group 2
Texture
It was a little tough to chew but a perfect consistency.
It was very hard
The crust was hard and chewy. It was soft in the middle.
The chart below shows the change in volume for each experiment before and after baking.
Nutrition Below is shown the daily nutrition percentage if one eats the baking soda loaf of bread. One can get most of one’s daily nutrients from this bread. Serving Size: 1 Loaf ● Calories 1400+240=1640. 66% of your daily usage nutrition. (= 1640/2500) ● Carbohydrates 4 g from sugar + 322 g from flour + 24g from butter milk = 350 g 88% of my daily usage nutrition. (= 350/400) ● Fat 6g. 7% of our daily usage. (= 6/78) ● Protein 50 g. 89% of my daily usage nutrition. (= 50/56)
Analysis: It appears the largest percentage change in volume came from our control group which was the yeast bread. Clearly, this releases the most amount of CO2. The percentage increase in volume for the yeast bread was 108%. This was far larger than that for sourdough, 28%, or the baking
soda bread, which was 60%. Bread is very nutritious. One can get most of one’s daily nutrition from a loaf of bread. This shows that bread was indeed very useful for the first farmers to grow flour and why the Agricultural Revolution was so important. Conclusion We did a control experiment making three loafs of bread with different leavening agents. The bread made with the yeast leavening agent showed the greatest increase in volume. Humans have been making bread with yeast for thousands of years so even though using baking soda is easier to make bread, it is better to make bread with yeast. Appendix Pictures of our breads after baking. Yeast Bread (Control Group)
Sourdough (Experimental Group 1)
Baking Soda Bread (Experimental Group 2)