Author: Maddie Van Beek

We’re taking science back in the kitchen!
 
Last blog we discovered how baking soda and baking powder affect our baked goods. If you want to bake some cookies and test it out for yourself, check it out here: Science of Baking Cookies. 

Today, we’re going to focus on a different leavening agent: eggs. First, let’s review what we already learned.
 
Baking soda vs. Baking powder:
Baking soda and baking powder are both leavening agents. Baking soda is usually called for in breads and cakes, while baking powder is more often seen in cookie recipes (although you will see either in all kinds of baked goods). The main difference is that baking soda requires an acid to react, while baking powder does not. Therefore, they are not interchangeable. If your recipe does not have acid, but you use baking soda, you won’t get the desired effects.
 
Why is this? Baking soda is a base—sodium bicarbonate. In order to react, it needs an acid to react with. Baking powder contains baking soda, but also contains a dry acid. This means it only needs liquid—almost any liquid will do—in order for it to react. When baking soda or baking powder react, the reaction produces carbon dioxide gas. This gas creates bubbles in your baked goods, which helps give them a fluffier texture.
 
What we found in our last experiment is that using baking soda in a recipe that called for baking powder resulted in flatter cookies. This time, you’ll do a similar comparison with eggs.
 
Before we move on, what exactly does leavening mean?
Leavening is the process by which dough or batter for breads, cookies, etc. rise or become fluffier. Some breads call for yeast, which takes longer to help the dough rise. Because yeast is actually a living organism, it is a biological leavening agent. Baking soda and baking powder are chemical leavening agents; they help dough rise through a chemical reaction. Another form of leavening is simply through steam. As liquid evaporates, steam rises through the dough, allowing the dough to rise too.
 
What purpose does an egg serve?

1. It adds liquid to your recipe. Thus, leavening through steam can occur.
2. When eggs are beaten into other ingredients, air is also incorporated. This also helps baked goods become lighter and more airy.

 
What’s in an egg?

• Protein
• Fat
• Water

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All these nutrients help bind the dough together. Without eggs, many recipes would produce a much drier, crumbly result.
 
Let’s test this out! You’ll bake two versions of banana bread—one with eggs, and one without.
 
Here’s the recipe I used:
 
If you’d like to pick a different recipe, go right ahead! Just make sure that the original recipe calls for eggs.
 
YOU WILL NEED:
 
Dry ingredients:

• ¼ Cup Whole Grain Flour
• ¼ Cup White Flour
• ¼ Cup Oats
• 1 Teaspoon Baking Powder
• ½ Teaspoon Baking Soda
• 1 Teaspoon Cinnamon
• 1 Teaspoon Nutmeg
• ½ Teaspoon Turmeric
• ¼ Cup Chocolate Chips

 
Wet ingredients:

• ½ Cup Almond Milk
• ¼ Cup Coconut Oil
• ¼  Cup Maple Syrup
• 1 Teaspoon Vanilla
• 2 eggs
• 2 mashed bananas

 
Utensils:

• 2 large mixing bowls for dry ingredients
• 2 medium mixing bowls for wet ingredients
• Muffin tin
• Non-stick spray
• Whisk or large spoon
• Measuring cups and spoons

 
Here’s what to do!
 
Mix up two batches of ingredients, one with eggs, and one where the eggs are left out. Make sure you measure each ingredient carefully so your recipes are exactly the same! Bake them at the same time, and make sure to flip the pan halfway through so each batch gets the same baking conditions. That way, you know the only variable in your experiment is the eggs (or lack thereof).
 

1. Pre-heat your oven to 375 degrees.
2. Spray your muffin tin with a non-stick spray.
3. Mix all your dry ingredients first. Repeat in a second bowl so you have one for each of your two batches. 

4. Whisk your wet ingredients in a separate bowl. (Why? It seems like a hassle to use more than one bowl, right? Remember, the wet ingredients activate the baking soda/baking powder, so you don’t want that to happen too early before putting your batter into the oven!) Repeat in a second wet ingredient bowl, except with NO EGGS. 

5. Slowly pour your wet ingredients into your dry ingredients. Stir until well mixed. 

6. Measure ¼ cup of the bread batter with NO EGGS into the left side of your muffin tin. Measure ¼ cup of the bread batter WITH EGGS into the right side of your muffin tin. 

7. Place in the oven and set timer for 20 minutes.
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8. Check back and see how they look so far. What do you notice? Flip the tin around so the muffins get equal baking conditions. I was surprised to see the egg muffins were rising less so far!

9. Remove from the oven at 40 minutes and let cool. Again, do you notice any differences in appearance? 

10. Carefully take the muffins out of the tin. Compare the differences in texture, taste, etc. 

​Results:
With this recipe, the baking soda and baking powder helped both the muffin batches rise about equally. There was, however, a clear difference in appearance. The egg muffins (right) were very uniform. The extra moisture from the eggs probably allowed the batter to settle into the muffin tin and rise more evenly. The non-egg muffins (left) were more misshapen and lumpy, with crunchier tops. The non-egg muffins were very easy to remove from the tin, while the egg muffins took a little extra prying. The egg muffins, when cut in half, were much more moist. They also felt lighter and fluffier. The non-egg muffins were drier and denser. 
 
What did you notice in your recipes? 

​Extension:
Next, test out the same recipe WITHOUT eggs, baking soda, or baking powder. What kind of results would you expect? Think back to what you’ve learned about the purpose of these ingredients.
 
Results: The third batch did not rise at all. It was much denser and heavier than either of the first two muffins. It didn’t brown nearly as much (baking soda also has a hand in helping baked goods brown). The surface had a chewier texture, and the center did not bake all the way through in the 40 minutes… it was kind of just mushy in the middle. 

​What did you find?
 
Happy baking, and happy muffin tasting! 

Author: Maddie Van Beek



What better way to learn about science than with COOKIES?! Today we are going to learn about the difference between baking soda and baking powder.



People often get confused about the difference between these two baking ingredients, and it’s no wonder! They look identical, and they serve the same purpose in baking. They are both used as leavening agents in cakes, cookies, and other baked goods. That means that they help baked goods rise and get that nice, fluffy texture. Even though they have the same purpose, they cannot be swapped seamlessly. Why not?


Well, baking soda (sodium bicarbonate), as you may know, is a base. When combined with acidic ingredients, such as lemon juice, vinegar, buttermilk, sour cream, etc., it reacts to create carbon dioxide gas.


Baking POWDER is like baking soda PLUS. It contains sodium bicarbonate, but it also has a dry acid already included, such as Cream of Tartar. This means that it can be used in recipes that don’t contain any acidic ingredients at all, but it will still react to create carbon dioxide once any liquid is added.


Let’s test this out!


Here’s a photo of both dry baking soda and dry baking powder.

On the left, we have baking powder. When warm water is added, the reaction occurs!

On the right, we have baking soda. Try adding water. Nothing! But, when you add vinegar (an acid), the reaction commences!

Another important note: Since baking powder is baking soda in addition to a second ingredient, it is not as powerful. Therefore, recipes calling for baking powder
require more than recipes calling for baking soda. A good rule of thumb is ¼ teaspoon baking soda = 1 teaspoon baking powder.


Remember though, you can’t easily swap these two leavening agents. You may be able to use baking powder in replacement for baking soda without disaster, but you will have to increase the amount, as stated above. The opposite is not true. If a recipe calls for baking powder, but you use baking soda instead, disaster (okay, maybe just flat cookies) may ensue. If there are no acids present in your recipe, the baking soda itself may not be enough to react.


The last big difference between baking soda and baking powder is the reaction time. Because baking soda reacts quickly, you need to work with haste! If you don’t get your batter in the oven soon enough, the reaction will be over, and your baked goods may be flat. Baking powder, however, often has a dual reaction. First, it reacts when a liquid is added. That liquid allows the baking soda and dry acid to combine and produce carbon dioxide gas. The second part of the reaction occurs when the batter is heated. Therefore, you don’t have to work quite as quickly. You actually can even let your batter sit in the fridge and not be ruined. By doing so, your cookies may be flatter than those baked right away, but they will not be as flat as they would had you used baking soda.


Enough talk, let’s get baking!


You’re going to make a classic chocolate chip cookie recipe that calls for baking powder. We will also make the same recipe with baking soda to see how swapping those ingredients make a difference in our outcome.


YOU WILL NEED:
* 2 large mixing bowls
* 2 small mixing bowls
* Hand mixer
* Measuring cups
* Measuring spoons
* Parchment paper or non-stick spray


Each batch of cookies (you will be making two) will call for the following amounts:
* 1 ¼ Cup Flour
* ½ Teaspoon Salt
* ½ Teaspoon Baking Powder (1/8 Teaspoon Baking Soda for the 2nd batch)

* ½ Cup Brown Sugar
* ¼ Cup White Sugar
* ½ Teaspoon Vanilla
* ½ Cup Butter
* 1 Egg


Here’s what to do!
1. You’ll get your baking powder batch ready first! Start by combining the dry ingredients: Flour, salt, and baking powder.

2. Melt the butter in the microwave (20 seconds should be good)

3. Add the brown sugar, white sugar, and vanilla. Start mixing!

4. Add the egg and continue to mix.

5. Slowly sift in the dry ingredients until your dough is well blended.

6. Add any chocolate chips or nuts that you would like to include.

7. Pre-heat oven to 350 degrees

8. Spoon the dough onto a greased cookie sheet.

9. Set the timer for 12 minutes.

10. Remove and see your results!

11. Now TASTE your results! Notice the differences in texture, appearance, etc. (The baking powder batch is on the left, the baking soda batch is on the right)

Conclusion: The cookies with baking powder were fluffier and had a cake-like texture.

The cookies with baking soda were much flatter, but not as flat as expected. Why? Because brown sugar is actually acidic due to the molasses in it, so that little bit of acidity allowed for the baking soda to still have some effect.


Now, if you want to take it a step further… find a recipe that calls for baking powder that includes NO acidic ingredients. Go through the two-batch process to see how much of a difference baking powder makes vs. baking soda.


NOTE: Eggs are also an aid in leavening. Try using a recipe that does not have eggs to see the most drastic results.


Happy baking and taste testing!