How the Cookie Crumbles... in Space

This project follows the Scientific Method. Review the steps before you begin.

Preparing Your Samples

1. You will test different amounts of the following three ingredients: Eggs, butter, and flour. For each ingredient, you will specifically test the effect of using none of that ingredient (e.g., no eggs) or using twice the normal amount of that ingredient (e.g., twice the normal amount of eggs). 
2. In your lab notebook, create a table similar to Table 1. This will help you keep track of the 7 different recipes you will test. The "normal" recipe here is based on the Nestlé Toll House Chocolate Chip Cookie recipe. All recipes should yield at least 9 cookies per batch. 

3. Gather and prepare all of the ingredients so that you are ready to bake the cookies. You could bake all 7 recipes in one day, or you could space them out over a few days. To produce results that can be best compared between the different recipes, test the cookies all based on the same timeline from when you baked them (e.g., test all on the same day they are baked, or all one day post-baking, etc.).  
   1. If needed, have an adult help soften the butter.
   2. If you need less than one whole egg for a recipe, crack the egg into a measuring cup, mix it with a fork, and measure the total amount in the cup from one egg. One large egg may be approximately 50 mL.
4. Have an adult help you preheat the oven to 375° Fahrenheit (F).  
5. Choose the recipe you want to test first and bake the cookies as follows:
   1. Cover a metal baking tray with an ungreased baking sheet (i.e., parchment sheet).
   2. In a small bowl, combine the flour, baking soda, and salt. Whisk the ingredients together, as shown in Figure 1, below.
   3. In a large mixing bowl, beat in the butter, granulated sugar, brown sugar, and vanilla extract until the mixture is creamy, as shown in Figure 2. (Beating is usually performed using a fork or whisk, and involves mixing the ingredients until they are well mixed.) Note that if you are testing Recipe 4, it may be less creamy because it includes no butter. 
   4. To the large mixing bowl, add the egg and beat well.
   5. Take the flour, baking soda, and salt mixture from the small bowl and gradually mix it into the large bowl.  
   6. Stir in the chocolate chips, as shown in Figure 3. Your cookie batter is now ready for baking.
   7. Using a tablespoon measuring spoon, measure and drop the cookie batter onto the prepared baking tray (covered with a baking sheet). Each cookie should be a rounded tablespoon (i.e., slightly more than one tablespoon).
      1. Tip: For some of the recipes, you may need to firmly press them into the measuring spoon for them to hold shape.
      2. Record any observations about the batter in your lab notebook, such as the batter's color, texture, and level of dryness.
   8. When the tray is ready, have an adult help you place it in the oven, which should be heated to 375° F. Set a timer for 5 minutes and check on the cookies after 5 minutes. Record any observations. For most of the recipes you are testing, you should bake the cookies for a total of 9 to 11 minutes, or until golden brown. Note: If your cookies brown more quickly, you may want to remove them sooner.
      1. In your lab notebook, record how many cookies you prepared for the recipe, how long you baked the cookies, and any other observations about how the cookies baked. 
   9. Have an adult help you remove the cookies from the oven when they are done baking.
   10. After the tray of cookies has cooled for 2 minutes, have an adult help you remove the cookies to further cool on a wire rack. Some cookies may be fragile, and you may want to use a spatula to carefully transfer them to the wire rack. Try to keep the cookies intact as much as possible while you transfer them.

Image Credit: Teisha Rowland / Science Buddies

Whisking bowl of dry cookie ingredients: flour, baking soda, sugar.

Figure 1. Small mixing bowl with flour, baking soda, and salt being whisked together.

Image Credit: Teisha Rowland / Science Buddies

Large mixing bowl with cookie batter with chocolate chips mixed in.

Figure 2. Larger mixing bowl with creamed butter, granulated sugar, brown sugar, and vanilla extract.

Image Credit: Teisha Rowland / Science Buddies

Large mixing bowl with cookie batter with chocolate chips mixed in.

Figure 3. Larger mixing bowl with cookie dough ready for baking.

6. Repeat steps 5a to 5j for each of the remaining recipes.
7. Wait until the cookies cool completely before moving on to the next steps.

Measuring the Crumbliness of Your Samples

1. In your lab notebook, create a data table similar to Table 2. Use a ruler or measuring tape to measure the diameter of at least five cookies from each recipe and record any other observations.
   1. How are the diameters of the cookies similar or different? Why do you think this might be? Do you think the shape and size of the cookies may affect how crumbly they are? 
   2. When recording other observations, consider the color, texture, odor, and any other properties of note about the cookies. Why do you think the cookies have different properties? How do the recipes and their ingredients seem to affect the properties of the cookies? Do they all seem like "cookies," or do they seem like other types of baked goods, such as possibly bread, shortbread, or peanut brittle? 

2. In your lab notebook, create a data table similar to Table 3. You will use this to record your results for the three different crumb tests. You should perform at least three trials, using one cookie for each trial.

3. Perform the "Drop test" as follows on at least three cookies for each recipe (be sure to save enough cookies for the other two crumb tests):
   1. Line the bottom of a large cardboard box with a layer of paper. You will be dropping the cookies into this box. The paper lining will make it easier to clean out the crumbs.
   2. Determine what height you want to drop the cookies from. We recommend using a height of at least 1 meter (m) (which is the same as 100 centimeters [cm]). Use the same height for each trial.
   3. For each trial, weigh the cookie on a digital scale before the test. Record the mass in the "Before" row for that trial.
   4. Drop the cookie into the box from the determined height.
   5. Pick up the largest cookie piece from the box and weigh the cookie. Record the mass in the "After" row.
   6. Record any other observations in your lab notebook.
   7. Repeat steps 3c to 3f for all recipes and trials, performing at least three trials per recipe. Use a new, untested cookie for each trial.
4. Perform the "Breaking in half test" as follows on at least three cookies for each recipe (be sure to save enough cookies for the last crumb test):
   1. For each trial, weigh the cookie on a digital scale before the test. Record the mass in the "Before" row for that trial.
      1. Use a new, untested cookie for each trial.
   2. Over a bowl, use your hands to break a cookie in half as evenly as possible.
   3. Weigh the large cookie pieces remaining in your hands (i.e., not the crumbs). Record the mass in the "After" row.
   4. Record any other observations in your lab notebook.
   5. Repeat steps 4a to 4d for all recipes and trials, performing at least three trials per recipe. 
5. Perform the "Shaking test" as follows on at least three cookies for each recipe:
   1. For each trial, weigh the cookie on a digital scale before the test. Record the mass in the "Before" row for that trial.
      1. Use a new, untested cookie for each trial.
   2. Place the cookie in a hard-walled box that is at least 25 cm on each side and seal the box. If the box is much smaller, it may not generate enough shaking force to make many crumbs. Tip: If it is challenging to create enough crumbs, you could try using a larger box.
   3. Vigorously shake the cookie in the box 30 to 50 times. 
      1. For each trial, shake the cookie the same number of times, and as similarly as possible.
   4. Weigh the large cookie pieces remaining in the box (i.e., not the crumbs). Record the mass in the "After" row for that trial.
   5. Record any other observations in your lab notebook.
   6. Note: If you have access to a vortex or a cell culture shaker (which are common pieces of equipment in many life science and chemistry research laboratories), you may be able to devise a way to use the vortex or shaker to more consistently "shake" the cookies for performing a shaking test.
   7. Repeat steps 5a to 5e for all recipes and trials, performing at least three trials per recipe.

Analyzing Your Data

1. In your lab notebook, create a data table similar to Table 4. You will use this table to help you record the results of your calculations and analyze your data. 

2. Take the data table in which you recorded the results of the crumb tests (Table 3) and calculate the percentage of cookie remaining in each trial. In other words, you are calculating how much of the cookie was not lost to crumbs. To do this, do the following:
   1. For each trial, divide the "After" mass by the "Before" mass. 
      1. For example, if the "After" mass is 16.5 grams (g), and the "Before" mass is 17.9 g, then you would calculate 16.5 g divided by 17.9 g, which equals 0.92 or 92%. This means that 92% of the cookie remained in big pieces (i.e., not crumbs).
   2. Write your results in the data table.
3. For each recipe, calculate the average of the trials. To calculate this, add together the "Percent remaining" results for each of the three trials and then divide the result by three (because you had three replicates, or trials). Write the results in your data table. 
   1. For example, if the results for each of the three trials were 92%, 94%, and 91%, the average would be 92%. 
   2. Advanced students can also calculate the standard deviations of their data and add these (as error bars) to their graphs.
4. Graph your results in a bar graph, with the recipe on the x-axis and the percentage of cookie remaining on the y-axis. You should make a separate bar graph for each of the three crumb tests. 
   1. If you want, you can also calculate and graph the average cookie diameter using the data you collected in Table 2.
5. Based on your results, which recipes generate the cookies with the greatest amount of crumbs? Why do you think this is? Did some recipes generate similar amounts of crumbs? Can you explain your results based on the differences in the recipes tested? Did your results surprise you? Why or why not?
6. What recipe(s) would you recommend using to bake cookies with the least amount of crumbs?
7. If you were to further improve one or some of the recipes you tested, what adjustments might you make to create even better cookies for astronauts?