Maillard Reaction
By Evelyn Lee
October 14, 2022
UPDATED 12:00 PM EST
Maillard Reaction
Photo credit: Food52.com]
If one is ever given, say, a cut of steak or a bushel of vegetables, and is asked to either boil or roast the ingredients, there’s a pretty good chance that they’ll choose to roast the food. Why is that the case? Well, the obvious answer is that baking, frying, or pan-searing things taste much better than simply boiling or steaming, but what’s the more chemical reason behind this?
The Maillard Reaction, named after the French chemist Louis Camille Maillard, occurs when the proteins and sugars inside and outside of food rearrange themselves into new chemical compounds. This results in your food taking on a more browned color. There are several factors that help create this reaction. For instance, the heat applied to the food needs to be high enough, and there can’t be too much moisture, or else browning will not occur. This is why boiled food never browns unless the water is evaporated enough– water can only reach a temperature at 212 degrees Fahrenheit under normal circumstances. For comparison, the Maillard Reaction’s optimal temperature is around 284 to 329 degrees Fahrenheit. After that threshold, burning and charring begin to occur. However, although many similarities can be drawn from the Maillard Reaction and the process of caramelization (mainly the browned color and a nuttier aroma), caramelization mostly concerns itself with the rearrangement and heating of sugars, while the Maillard Reaction relates to both sugars and amino acids.
In terms of chemicals, there are two main components necessary to undergo the reaction. Since proteins are all made of amino acids, an amine (-NH2) group is typically a main contributor to the Maillard Reaction. Furthermore, a reducing sugar, which has a free aldehyde or ketone group that can reduce (or add electrons) other compounds, also reacts with the amino acids to form new compounds. Common reducing sugars include glucose, fructose, and lactose.
By rearranging different proteins and sugars in food, the Maillard Reaction can create several important compounds crucial for the taste and color. One notable example is melanoidins, which (as its name suggests) contribute to the browned color and the distinct smell of seared meat or vegetables. This Maillard Reaction product (MRP) is relatively harmless, but other MRPs, such as acrylamide, have been identified to act as a carcinogen. Acrylamide is very prevalent in Maillard-ified foods, and is likely to accumulate over long periods of cooking or over high heat. Unlike melanoidins, acrylamide tends to only occur in plant-based foods, such as potatoes in potato chips, grain products, and coffee beans.
References
Krystal, Becky. “The Maillard Reaction: What It Is and Why It Matters.” The Washington Post, 31 Jan. 2020, www.washingtonpost.com/news/voraciously/wp/2020/01/31/the-maillard-reaction-what-it-is-and-why-it-matters.
Schulze, Eric. “An Introduction to the Maillard Reaction.” Serious Eats, 25 Sept. 2019, www.seriouseats.com/what-is-maillard-reaction-cooking-science.
Tamanna, Nahid, and Niaz Mahmood. “Food Processing and Maillard Reaction Products: Effect on Human Health and Nutrition.” International journal of food science vol. 2015 (2015): 526762. doi:10.1155/2015/526762