It’s easy to be captivated when you look at a perfectly seared steak and see its dark brown exterior coupled with an expertly cooked, pink and juicy centre. The brown sear promises complex flavours and textures in your food which only serve to beguile you further as you stare lovingly at the cooked meat.
This is all possible thanks to French chemist Louis Camille Maillard and his discovery of the Maillard reaction back in 1912. It is this reaction that transforms red and bloody raw meat into something more appealing to eat.
The Maillard reaction is critical to the proper preparation of almost any cooked food. It is responsible not only for the sear on your steak but also the brown and toasty exterior of your bread, the dark and roasted flavour of your coffee, and you can even thank the Maillard reaction for providing the hoppy taste of your favourite beer.
What is the Maillard reaction?
If you take a black and white look at food, you can break it down into a series of proteins, sugars, and water. The Maillard reaction is what occurs when you introduce prolonged heat to these building blocks and cause them to join together and fundamentally change their chemical composition into something almost completely different with new flavours, smells, and colours.
It may sound complicated but that’s only because it is. We can simplify it down to just proteins and sugars changing state when exposed to heat but the real science behind the Maillard reaction wasn’t truly understood until almost 50 years after it was originally identified.
What we do know for sure though is that the Maillard reaction makes food a whole lot more appealing to us by making food look a lot more nutritious and “safe” from an evolutionary perspective.
While it is the most commonly occurring reaction in the world, according to Nobel prize-winning chemist Jean-Marie Lehn, it is easy to take for granted the effect it has on us. You may be prone to forgetting it is happening but you will sure notice when it doesn’t happen.
Picture in your mind a steak that has been boiled all the way through, its grey and flaccid appearance giving just a small window into the truly awful taste and texture it holds. It looks and tastes this way because the Maillard reaction has not occurred in the relatively low temperature of boiling water.
But hold it right there, it gets even more complicated. The absence of high heat does not mean the absence of the Maillard reaction. With enough water and a long enough period of time, a relatively low heat can still produce the reaction. For example, if you leave a stock to simmer for 14 hours you will invariably come back to a much more flavourful and darker liquid. There's your low-temperature Maillard.
The Keys To The Perfect Reaction
Heat, water, and time are the three keys to achieving the Maillard reaction and adding lots of flavour to your meals if applied to the proper building blocks of proteins and sugars found in the food itself.
Proteins in the food are made of Amino acids that are chemically predisposed to joining with sugar molecules. That doesn’t mean that sprinkling your filet with sugar will produce a better sear though, it takes a special kind of Maillard-susceptible sugars with much smaller molecules that are ideal for attracting and bonding to Amino acids when placed under the correct heat and moisture levels.
Don't be dissuaded by the seemingly unscalable wall of chemistry though. The home cook still maintains a great deal of control over how the Maillard reaction takes place and a thorough understanding of the process will unlock your full cooking potential as you mix and match the factors involved.
If you’re looking for a browner sear then lower the moisture levels and up the heat. How about a more evenly cooked piece of meat? Drop the temperature and increase the exposure time.
Once you get that understanding of how your food comes to be, cooking becomes less of a box-ticking exercise and more of an exciting adventure.
Maillard Is Everywhere
Further up in this article we noted that the Maillard reaction is the most commonly occurring reaction in the world. It’s happening in kitchens in every corner of the globe right now as you read this. If you’re cooking tonight then the chances are that you’ll be using it yourself.
Even if it doesn’t seem like it, Maillard's reaction is absolutely everywhere.
Eric Shultz PhD is, amongst other things, a respected molecular and cellular biologist who has written extensively about the Maillard reaction. He uses the example of the humble potato to illustrate how it can be found in almost every concoction of food.
An uncooked potato is an unappealing sight to most but when chopped up and roasted it produces one of my favourite side dishes. The heat of the oven removes the moisture from the surface of the chopped potatoes and begins to break the starches down into a more simple sugar. The heat will continue to increase due to the lack of moisture which breaks down the sugars and proteins even more until they eventually combine.
Before you know it, you find yourself with crispy brown potatoes with a wafting aroma that fills your nose with pleasure and sends that rush of endorphins through your system as your brain recognises the smell as safe and nutritious sustenance. This is the Maillard reaction that we are most familiar with.
Take a look at mashed potatoes though. Boiled in water for a short amount of time, these potatoes are decidedly un-Maillarded, some people reading this may love the taste of plain mashed potatoes but to many, it is simply boring. It is only when you add other flavours and aromas do they become exciting. Eric Shultz notes that with the addition of butter, mashed potatoes go from bland to delicious. This is because the principle flavour in butter is butyric acid with its butyrates. These butyrates are also the primary aroma producing molecules that are formed when meat is roasted and undergoes the Maillard reaction. Whichever way you look, Maillard is there.
It is really worth your time getting to grips with the Maillard reaction, its causes, its effects, and how to influence it. We hope this article, while in no way being exhaustive because we’re not here to read a scientific journal, has helped your understanding in some way and has introduced you to new concepts in the kitchen.
Remember, cooking strictly from a recipe is a sure-fire way to never improve your skills. It's important to step out of your comfort zone in the kitchen every once in a while and get to grips with new ideas. Now you have a hopefully deeper understanding of what’s going on in the pan, give it a try yourself and see what you can come up with!