Chocolate Chip Cookies: Science-fied!

The following recipe for chocolate chip cookies was adapted from a recipe that appeared in Chemical & Engineering News (C&EN, June 19, 1995, p. 100). It was attributed to Jeannene Ackerman of Wico Corp. The recipe was published in Fisher Science Education's March/April 2013 issue of Headline Discoveries.

Ever wonder what a chocolate chip cookie looks like from a chemist's perspective? 

The ingredient list will probably look a lot like this:

• 532.35mL (283 grams) finely milled wheat grains
• 4.9mL NaHCO₃
• 4.9mL refined halite
• 226.8 grams (2 rectangular prisms) partially hydrogenated tallow triglyceride
• 177.45mL crystalline sucrose (C₁₂H₂₂O₁₁)
• 177.45mL sucrose-molasses mixture
• 4.9mL vanillin-ethanol solution
• Two calcium carbonate-encapsulated avian albumen-coated protein
• 473.2mL theobroma cacao

And here's how a chemist would go about making these ooey-gooey favorites:

1. Add the finely milled wheat grains, NaHCO₃ and refined halite to a 2L jacketed round reactor vessel (reactor #1) equipped with a sir mechanism.
2. In a second 2L reactor vessel fitted with a radial flow impeller operating at 100 rpm, app the triglyceride, sucrose, score-molasses mixture and vanillin-ethanol solution until the mixture is homogenous.
3. Add the encapsulated albumen-coated protein followed by three equal portions of the homogenous mixture in reactor #1. Add the theobroma cacao slowly with constant agitation. Care must be taken at this point in the reaction to control any temperature rise that may be the result of an exothermic reaction.
4. Divide the resulting slurry into spheres each approximately 65mL in volume. Place individual spheres on a 316 SS sheet (300 x 600mm). Heat in a 450°K oven for a period of time that is in agreement with Frank & Johnston’s first order rate expression (see JACOS, 21, 55), or until golden brown.
5. Once the reaction is complete, place the sheet on a 300°K heat-transfer surface allowing the product to come to thermal equilibrium.

Want to take this recipe (or yummy experiment, whatever you'd like to call it) to the next level? Think about these discussion points: 

• If you wanted to add peanuts or dark chocolate to your cookies, what would you add to the list of ingredients?
• Write your own chemist's recipe for a baked treat using the format above.

Make a Patriotic Density Column in Honor of the Fourth of July!

Trying to figure out what you're going to do in between the morning parade and the evening fireworks tomorrow? Right before you head out to grill some burgers or join some friends at the park, intrigue your children (and yourself) with a patriotic science lesson!

This July 4th chemistry lesson celebrates America and ends up being a red, white and blue display of density layers. (Note: Kerosene lamp oil is toxic and flammable. Because this experiment includes using kerosene lamp oil, adult supervision is required.)

Here's what you'll need:

• Milk
• Red Kerosene Lamp Oil (Sold at your local home improvement store)
• Light Corn Syrup
• Blue Food Coloring
• Clear column or cup

Here's how you'll do it:

1. Mix blue food coloring into the corn syrup until the desired color is attained.
2. Slowly pour the same amount of the colored corn syrup, kerosene lamp oil and milk (in any order you wish) into a clear column or cup. Here's a hint: You get minimal mixing by slowly pouring each liquid over the back of a disposable plastic spoon.
3. Now observe and enjoy! The most dense liquid is at the bottom of the column or cup and the least dense liquid is at the top. Were you predictions about the order of the colors correct?!

To make the density column more exciting, light the top layer (the lamp oil) on fire!

*Fuel kerosene is also sometimes available in a blue color, so if this is what you have, use it and just make the light corn syrup red with food coloring.

Check out this video for a demonstration of a patriotic density column. 

This woman makes her's in a shot glass!

Girl Scouts Attend "Cool Science"

U.S. Air Force photo by Julie Imada

Just last week, approximately 50 girls experimented with liquid nitrogen, Alka Seltzer rockets and food chemical mixtures at the U.S. Air Force Academy in Colorado. Supervised by cadets, these girls were ages 5-7 and all belonged to Girls Scout Daisy and Brownie troops. At the Academy's workshop - titled "Cool Science" - the girls were able to see first hand how fun science can be through creative chemistry and physics experiments illustrated by the cadets.  Can I get three cheers for the Air Force Academy?! 

The Girl Scouts spent the day at the Academy working on simple hands-on, educational experiments like how to make ice cream with liquid nitrogen, how a film canister reacts with Alka Seltzer and how many chemistry books a tower constructed of paper and masking tape can support. 

Cadet 4th Class Katherine Case saw the bigger picture when she said, "It's an important event because ti gives an introduction to young girls about the world of science, which is important because there aren't many females in the field."  She added, "when I was younger, I went to something called 'Girls in Engineering and Mathematic Science' that presented workshops on career fields in science and made me fall in love with the field. Now I'm pursuing that love."

These are the type of programs that we need to see more of! Programs that ignite an interest in STEM fields and leave young students with the desire to pursue a career in STEM. While it's important to target girls when they're young so that they don't grow up thinking that STEM fields are for boys, there should still be a push to get boys just as interested and fired up about STEM. 

The Air Force Academy has hosted this workshop every spring and fall for 10 years and hopes it continues to be a hit. Read more about the Nov. 10 workshop.

Do you know of great programs in your area that encourage young people to take an interest in STEM fields? Subscribe to our blog and let us know and you could win a Starbucks giftcard!