Flavor Occurs between 230℉ and 340℉: The Maillard Reaction Erica Wahe, Independent Member, 11th grade 10445 Food and Nutrition Report (7th Year in Food and Nutrition) County: Johnson County
What does toast, cookies, ribs, and popcorn have in common?
The Maillard Reaction, which is also known as the browning reaction is why lots of cooked foods form a different flavor, coloring, and scent after cooking. It occurs between sugars in food rich in carbohydrates (like glucose in bread) and amino acids (like valine, lysine, and glycine). The reaction creates thousands of compounds which then reaction with one another to create the flavors, colors, and scents of cooked foods. The reaction was coined by Louis Maillard who was a chemist in the 20th century. This reaction is non-enzymatic, which means that there is no enzyme that reduces the energy threshold for the reaction to take place. The reaction works at temperatures from 230F to 340F degrees as the chemical reaction rate is faster and the excess water molecules in the food evaporate. Any temperature over 340F degrees may create burnt or charred flavors. The food must also have sugars and amino acids for the reaction to take place. If there are no amino acids and only sugars; caramelization may take place. Caramelization and the Maillard Reaction are distinct despite the similar final results. pH can also be a factor, increasing the pH in certain foods like onions (adding baking soda as it is basic) can make the reaction quicker and enhance the flavor.
The mechanism for the Maillard reaction was established by John Hodge, an employee of the Department of Agriculture. His model shows the Maillard reaction in three stages. First, the carbonyl group of a sugar reacts with an amino group on a protein or amino acid to produce water and an unstable glycosylamine. Then, the glycosylamine undergoes Amadori rearrangements to produce a series of aminoketose compounds. The aminoketose compounds undergo a host of further rearrangements, conversions, additions, and polymerizations creating molecules, including some that convey flavor, aroma, and color. The Maillard reaction is actually a group of reactions that creates the thousands of different compounds that we recognize as flavor, scent, and color.
The basis of the Maillard reaction is that it creates appealing colors, flavors, and scents of cooked food which means the end result can be influenced by additives. Industrial scale food needs to be likeable and have a long shelf life so adding different amino acids and sugars can create palatable processed food. Artificial flavors can be produced due to the Maillard Reaction because the type of amino acid determines the flavor of the food. Processed food is not the only product of the Maillard Reaction and at least two carcinogens 5-hydroxymethylfurfural (HMF) and acrylamide have been discovered. The cancer causing nature of the process is concerning and could be alleviated by a lower cooking temperature, but consumers dislike a lighter coloring in products such as cookies or bread. The reaction even happens inside human tissue and is linked to diabetes and cataracts.
The Maillard reaction is pretty delicious science. The final flavor depends on cooking time, temperature, types of amino acids and sugars in the food. Cooking food kills bacteria, increases shelf life, creates flavors, scents, colors, but the process also creates harmful compounds in the food we consume every day.
Goals
My goal is to learn why toast tastes so much better than normal bread by fairtime. My goal is to write a paper over the Maillard reaction by fairtime.
Process
I got this idea from my chemistry teacher. She overheard me commenting on how great toast is and told me that there is a chemical reaction involved. I decided to do more research on the subject. After looking online, I watched a show called “The Science of the Sizzle”. It was definitely geared towards cooking meat, but covered some food science that I found interesting. I then watched another show called “Alton’s Porterhouse Perfection”. It was similarly geared towards meat, but explained how to maximize the reaction for cooking. I also read some articles to learn about the technical aspects of the reaction. I read the paper John Hodge wrote about the mechanism in the Maillard Reaction to understand the science behind it. I found the journal incredibly interesting, but really hard to understand. An article on the reaction in Chemical and Engineering News Journal made it easier to understand. I am a bit curious about adding different amino acids and sugars to foods to change the flavor to make artificial flavors myself. There is not much information I found, and I think it may be due to the proprietary processes of making the artificial flavors and processed foods. I really liked learning about food science and I am now looking into a career in the field.
Things Learned
I learned that the reaction is not a singular reaction between one type of amino acids and one type of sugars, but a collection of reactions. I learned that both caramelization and Maillard reaction can occur together as long as there are amino acids and sugars. I learned that increasing the pH of onions with baking soda increases the rate of reaction and flavor. I learned that John Hodge discovered the science behind the Maillard Reaction and that it is very complex. I learned why toast tastes so much better than once cooked bread. I learned that food science is a field of study and a possible career. I learned that the Maillard reaction can occur in humans causing conditions like diabetes and cataracts along with making carcinogenic compounds.
APA Bibliography
Science of the Sizzle. 2017. [video] Directed by M. Mosley. Italy: PBS.
Mallawaarachchi, V., 2017. M aillard Reaction — The Science Of Browning, Flavoring And Aroma. [online] Medium. Available at:
Alton's Porterhouse Perfection. 2010. [video] Directed by A. Brown. Food Network.
Moyer, M., 2013. Why Does Food Taste So Delicious?. S cientific American, [online] Available at:
Hodge, J. (1953). Dehydrated Foods, Chemistry of Browning Reactions in Model Systems. Journal Of Agricultural And Food Chemistry, 1 ( 15), 920-950. doi: 10.1021/jf60015a004
Scienceofcooking.com. 2018. W hat Is The Maillard Reaction. [online] Available at:
Everts, S. (2012). The Maillard Reaction Turns 100. Retrieved 13 April 2020, from https://cen.acs.org/articles/90/i40/Maillard-Reaction-Turns-100.html
Modernistcuisine.com. 2013. T he Maillard Reaction. [online] Available at:
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