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:
- Add the finely milled wheat grains, NaHCO3 and refined halite to a 2L jacketed round reactor vessel (reactor #1) equipped with a sir mechanism.
- 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.
- 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.
- 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.
- 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.
