The Chemistry of Baking Cookies

WRITTEN BY SHRUTIRUPA SAHA

ILLUSTRATED BY CASSANDRA CHANG

May 20, 2026 | | 5 min read
A Rundown of Broma’s Bakery’s Chocolate Chip Cookie Recipe

The scene is set: it is Week 4, and midterms are in full swing, you are somewhere juggling exhausting study schedules, numerous assignments, finishing up last minute edits to lab reports, and rewatching your chemistry lecture videos- stress is high. And yet, inexplicably, you decide to bake chocolate chip cookies. For many, baking is a well-known destressing ritual.  However, little is known about the fascinating and complex chemistry quietly happening inside the mixing bowl. 

Though it may be used as an escape from the stresses that classes, especially chemistry may give, the process of baking is not very different from the processes one does in a chemistry lab. With every step of baking these chocolate chip cookies, the chemistry one already studied is being directly applied!

With the mixing bowl as one’s round bottom flask, and the oven as a hot plate, the cookie, if the experiment goes correctly, is the purified product in completion. 

Browning the Butter: A Maillard Reaction 

My go-to recipe for chocolate chip cookies is always Broma Bakery’s chocolate chip cookie recipe! The cookies are buttery and chewy with perfect texture! The secret to achieving these cookies is actually rooted in chemistry! The recipe begins with browning butter over a medium heat until it turns golden. The dairy parts of butter, which are casein proteins and lactose, undergo Maillard reactions. In Maillard reactions, amino acids and reducing sugars react to produce melanoidins, which are the “browned” components. Lactose, a reducing sugar, reacts with amino groups on the casein proteins through nucleophilic addition to the carbonyl carbon. This forms a hemiaminal which gets dehydrated to get a Schiff base product that undergoes an Amadori rearrangement to get the melanoidin product. 

Mixing the Wet Ingredients: 

Once the butter is browned, it is mixed with brown sugar, granulated sugar, and eggs. The molasses of brown sugar are hygroscopic, meaning they attract and retain water, allowing for the final product of the cookie to be chewy. This is similar to the use of desiccants and a dessicator in general chemistry and organic chemistry labs, which absorb moisture from the product. The eggs contain lecithin which is a phospholipid surfactant that prevents the batter from separating, 

Mixing the Dry Ingredients: 

Then, the flour, baking soda, and salt are combined separately before being added into the mixture of wet ingredients. This addition is controlled, similar to how some reagents are added dropwise in chemistry labs.  Glutenin and gliadin, components of flour are crosslinked into a viscous and elastic gluten network which is a 3D polymer which works to give the cookies a firm structure. The addition of baking soda or sodium bicarbonate (NaHCO3), gets decomposed to sodium carbonate, water, and carbon dioxide and also undergoes acid-base neutralization with the mildly acidic molasses from the brown sugar. The sodium carbonate product coupled with the high pH product from the neutralization, enhances the Maillard reaction. 

Baking the Cookies: 

When the cookie dough is set into the oven, the fats from the dough melt and gas is released to allow the cookies to rise. The sugars added caramelize and the protein from the eggs coagulate to solidify the cookie and the Maillard reaction produces the brown color of the cookies. 

Similar to working in a lab, baking chocolate chip cookies is also like a stepwise multi stage synthesis including reactions of Maillard reactions, emulsification, polymer network formation, acid-base neutralization, and thermal reactions, to produce a successful single product. Any mistake including wrong ratios, over-baking, or poor temperature control, the product can get messed up similar to missteps in the lab. So next time exam season sends you rushing to the kitchen to destress, just know that you are not escaping chemistry, you are embracing it. 

References
  1. Science of making brown butter sauce. www.scienceofcooking.com. https://www.scienceofcooking.com/science-of-cooking-with-brown-butter.html.
  2. Tamanna, N.; Mahmood, N. Food Processing and Maillard Reaction Products: Effect on Human Health and Nutrition. International Journal of Food Science 2015, 2015 (526762), 1–6. https://doi.org/10.1155/2015/526762.
  3. American Egg Board. Emulsification. American Egg Board. https://www.incredibleegg.org/professionals/manufacturers/real-egg-functionality/emulsification/.
  4. Brookshire, B. Cookie Science 13: The deal with gluten. Science News Explores. https://www.snexplores.org/blog/eureka-lab/cookie-science-13-deal-gluten.
  5. christina.marsigliese. THE BEST Bakery Style Chocolate Chip Cookies (with VIDEO) – Scientifically Sweet. Scientifically Sweet. https://scientificallysweet.com/the-best-chocolate-chip-cookies-bakery-style/.
  6. Vachon, P. Understanding the Science of Cookies | Institute of Culinary Education. Ice.edu. https://www.ice.edu/blog/understanding-science-cookies.