Page 1

Leavening Agents PA Partners: YJ and BD 9 May, 2018 INTRO. The question we are trying to answer is “Which leavening agents rise our bread the most?” My hypothesis is that the Bread made with yeast will rise the most because that's what yeast is made for to make bread rise. The other leavening agents are not made for rising bread. So in this AP we had to make bread and use a source to bake our bread. The ingredients are the measurements and what we used to bake our bread like flour. The Procedure is how to make the bread and what you should do. Lastly the Calculations are how we converted the loaves into one loaf. INGREDIENTS: Dennis bread -1/2 tablespoon active sourdough starter -​¼ cups​ all-purpose flour or bread flour -​⅙ cups of water

-½ t​ablespoon salt -​1 ½ cups of water

-2 ¾ cups of ​all-purpose flour or bread flour Yeast -​3 Cups Water

-6.5-7.5 cups all-purpose flour -1 tablespoon salt -1.5 tablespoons yeast Baking Soda -​3 1/2 cup all-purpose flour, plus extra for dusting

-1 teaspoon sugar -1 teaspoon baking soda -1 teaspoon salt -1 1/2–2 cups buttermilk Homemade Sourdough -​3 ⅓ cups flour -4/3 to 1 ½ cups of water -1 ⅙ teaspoons of salt -¼ cup starter Commercial Sourdough -​ 1/3 cup sourdough starter

-1 scant tablespoon -1 - 1 1/2 cup water -3 1/3 cup white flour

PROCEDURE: Dennis’ Sourdough ● ● ● ● ● ● ● ● ●

Make sure your sourdough culture is active Make the leaven (overnight) Test that the leaven is ready Dissolve the salt Mix the leaven and water Add the flour Rest the dough (30 minutes, or up to 4 hours) Mix in the salt Begin folding the dough (2 1/2 hours)

● ● ● ● ● ● ● ● ● ● ● ● ●

Let the dough rise undisturbed (30 to 60 minutes) Prepare 2 bread proofing baskets, colanders, or mixing bowls Shape the loaves Transfer to the proofing baskets Let the dough rise (3 to 4 hours, or overnight in the fridge) Heat the oven to 500°F Transfer the loaves to the Dutch ovens Score the top of the loaf Bake the loaves for 20 minutes Reduce the oven temperature to 450°F and bake another 10 minutes Remove the lids and continue baking 15 to 25 minutes Bake another 15 to 25 minutes Cool the loaves completely

Yeast ●

● ● ●

● ● ● ●

● ● ●

Combine all of the ingredients in a large mixing bowl, For first-timers, "lukewarm" means about 105°F.Mix and stir everything together to make a very sticky, rough dough. If you  have a stand mixer, beat at medium speed with the beater blade for 30 to 60 seconds.  Next, you're going to let the dough rise, just let it stay there, covering the bucket with a lid  or plastic wrap. Cover the bowl or bucket, and let the dough rise at room temperature for 2 hours. Then  refrigerate it for at least 2 hours, or for up to about 7 days. When you're ready to make bread, sprinkle the top of the dough with flour; this will make it easier to grab a hunk. Grease your hands, and pull off about 1/4 to 1/3 of the dough.  It'll be about the size of a softball, or a large grapefruit.  Plop the sticky dough onto a floured work surface, and round it into a ball, or a longer log. Place the loaf on a piece of parchment; or onto a lightly greased or parchment-lined  baking sheet. Sift a light coating of flour over the top.  Let the loaf warm to room temperature and rise; this should take about 60 minutes or  longer. If you're using a baking stone, position it on a middle rack while the oven preheats. Place a  shallow metal or cast iron pan on the lowest oven rack, and have 1 cup of hot water ready  to go. When you're ready to bake, take a sharp knife and slash the bread 2 or 3 times, making a cut about 1/2" deep. Place the bread in the oven and carefully pour the 1 cup hot water into the shallow pan on  the rack beneath. Bake the bread for 25 to 35 minutes.

Remove the bread from the oven, and cool it on a rack. Store leftover bread in a plastic bag at room temperature.

Baking Soda​: 1. Preheat oven to 450 fahrenheit 2. Place flour, sugar, baking soda, and salt into a large bowl and whisk together. 3. Make a well in the center and pour in most of the buttermilk, leaving about ¼ cup in the measuring cup. Using a fork, or one hand with your fingers outstretched like a claw, bring the flour and liquid together, adding more buttermilk, if necessary. Don’t knead the mixture, or it will become heavy. The dough should be soft, but not too wet and sticky. 4. When the dough comes together, turn it onto a floured work surface and bring it together a little more. Pat the dough into a roundabout 1½ inches thick and cut a deep cross in it. Place on a baking sheet. 5. Bake for 15 minutes. Turn down the heat to 400° and bake for 20-30 minutes more. When done, the loaf will sound slightly hollow when tapped on the bottom and be golden in color. One way to check if your bread is done is to use a thermometer. Cook until temperature in center reaches 195-200 degrees.

Homemade Sourdough:

● ●

Active starter has been left to ferment from 4–8 hours after a feed and is full of bubbles. To reach this point you need to begin 16 hours or so before you want to make dough. Say at about 3pm the day before I want to bake, I take 1 tablespoon of starter, mix with 2 tablespoons of flour, 1 tablespoon of water and mix it together, let it sit at room temperature for 8 hours or so. At about 10 or 11 p.m., before I go to bed, I feed it again by adding 8 tablespoons of flour and 5 tablespoons of water. I measure out what I need (3/4 cup for this recipe), put the remaining 1 tablespoon into a clean, loosely lidded jar and put it back in the fridge. Next​ morning, about 8 hours after the second feeding, the starter is ready to be incorporated into the dough.

Make the dough

● ●

Kneading is key to good bread. Wheat flour contains gluten and gliadin, proteins that, when hydrated and kneaded, turn into long, elastic, extensible chains, which trap the CO2 produced by yeast during fermentation. It is not critical exactly how wet or dry the dough is. I can vary my 'same recipe' greatly just by changing the amount of water in the dough. Dry dough gives a denser texture or 'crumb;' wet dough a more 'open' and springy one. With this recipe, start by adding 4 cups of water, then the extra half cup in increments until you get a dough that doesn't feel too ​tight​. Flours vary in how much water they absorb, both according to the type of wheat and daily humidity. Hence it's impossible to give precise amount of water. It's all in the hands—after a few batches you'll be able to ​feel​ if the dough is too wet, too dry, or just right. So mix all the ingredients except salt—just enough to incorporate everything. Then let the dough rest—anywhere from 15 to 60 minutes. That gives the flour time to fully absorb the water, the protein chains to lengthen and relax, and fermentation to begin. That 'conditioning' means less kneading! Time to add salt. (If I'm not using a recipe, I figure 1 tsp of salt for every 1.5 lb loaf. This is the only place where the amount is fairly critical.) Salt improves the texture of the dough by toughening the gluten, but it also inhibits fermentation, which is why it's good to add it as late as possible. There are many ways to knead, but basically, you're aiming at turning the 'shaggy mass' of just mixed dough into a cohesive, elastic, smooth ball. 10–15 minutes of kneading is required. Don't add too much flour! Many people don't like sticky fingers and mess. This results in them adding flour and more flour 'til nothing sticks. And that results in a dull and boring loaf. Loaves, as with love, do better with lubrication. The wetter the better, both to stop the dough sticking and to improve hydration. So dip your hands in water whenever you find them dragging in the dough (scrape them clean in-between times too). To test if the dough has been kneaded enough, take a small handful and stretch it out with both hands like a piece of rubber balloon. If it thins into an even, translucent sheet, it's kneaded. If it's just ropy and tears apart, knead more. I wait until the very end to add spices, herbs, sesame seeds or dried fruit, since some spices inhibit fermentation, and seeds and nuts can tear up the dough and reduce the volume of the loaf. I knead them in gently and quickly.

Commercial Sourdough: 1. Mix the sourdough starter, flour, and salt together. Add 1 cup water and then more as needed to make a moist bread dough. 2. Knead the dough until it passes the “window pane test” (about 20 minutes): a small piece of dough will stretch between 4 fingers without breaking thin enough to allow light to pass through. 3. Shape the dough into a loaf. Place it in a pan, proofing basket, or on a board. Cover the dough lightly with a towel and allow the dough to rise for 4-24 hours. 4. Slice an X shape in the top of the loaf with a very sharp knife or razor blade.

5. Bake at 400°F for 30-60 minutes, depending on the size of the loaf, until the internal temperature reaches 210°F (use a meat thermometer inserted into the bottom or side of the loaf). Cool before slicing. CALCULATIONS: The recipe we used made two loaves of bread and we only needed to make one. What we did was divide everything by 2. Dennis’ Sourdough: 1. Sourdough starter: 1 --> 1/2 2. Flour: 5 ½ --> 2 ¾ 3. Water: ⅓ --> ⅙ 4. Salt: ½ --> ¼

Commercial Sourdough​: N/A because the ingredients stayed the same

Homemade sourdough​: 1. 10/3 = 3 1/3 2. 4/3 | 9/2 / ⅓ = 1 ½

3. 7/2 / ⅓ = 7/6 4. ¾ /3 = ¼ Baking soda​: N/A because the ingredients stayed the same


1. 3/3.5= 1 cup ​2.​ ​6.5/3.5= 2.5

​3.​ ​1/1 = .5

​ 4.​ 3.5/1.5=2


Dennis’ sourdough: Before the bread was baked it was 1 ½ inches tall but when it was baked it go to be 3 ½ inches tall. The outside of the bread was really hard but on the inside it was a little raw. I think our bread was the most sour out of everyone's bread. Yeast: When the yeast group was about to bake it was 1 inch tall and after they bake their bread it was 2 ½ inches tall. It was the second shortest bread out of all five. I thought it would be the tallest because it's the most common leavening agent but I guess I was wrong. I think it was the best tasting one. Baking Soda: Before the bread was baked it was 1 ½ inches tall and after the bread was baked it was 3 ½ tall. This was a really good tasting bread because it wasn't sourdough. It was pretty soft and looked like real bread. Homemade Sourdough: Before the bread was baked it was 2 ½ inches and after it was baked it was 3 inches. This bread isn't the best and didn't really look like a bread because it was pretty flat. Commercial Sourdough:

This bread didn't rise as all. Before it was baked it was 1 inch and after it was baked it was 1 inch. I'm not sure why this happened but it looked similar to the Homemade Sourdough. Even though this bread was really flat it was one of the best tasting breads.

PA (2018) Leavening Agent Rising Chart

1. Flour: Carbohydrates:

​.25 cups ​ = 3 ​ .25 cups​

22 grams = Protein:

​.25 cups ​ = ​3.25 cups​

3 grams =




​.25 cups ​ = ​3.25 cups ​

100 cal =


.25x = 71.5 x = 286 grams .25x = 9.75 x = 39 grams

.25x = 325 x = 1,300 calories

1. Salt: Sodium:

​.25 teaspoon​ = ​.25 teaspoon​ 590 mg


x = 590 milligrams


Conclusion: Before doing this experiment I made a hypothesis which was “the Bread made with yeast will rise the most because that's what yeast is made for to make bread rise.” My hypothesis was proven wrong. It was wrong because the yeast was the second smallest bread out of all five. I think this AP was really fun and a good experience. If I can make the bread again I think I would make a different kind of bread because it took really long to make. Otherwise I think this AP went well for me and my group.

Dennis’ sourdough


Commercial Sourdough

Commercial Sourdough

Baking Dough   


Bread ap  
Bread ap