What is the Maillard reaction?

And why does the Maillard Reaction make everything delicious?

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By Max Bender

maillard reaction

The Maillard reaction is one of the most important phenomena in cooking that many may not be familiar with, but is responsible for the formation of the flavors and aromas in a variety of cooked foods (not all cooked foods, as we will see).

Let’s find out more about this intriguing phenomenon.

What is the Maillard reaction, exactly?

Imagine these three foods: a freshly baked cake, a rare steak, and just-baked bread. What do they have in common? Yes, exactly—they are all cooked, and more importantly, they have that appealing brown crust on the outside that we all love. Would we ever consider eating any of these three foods raw? They might not be so appealing, right?

The outer crust is the most delicious part of foods, and it’s delicious because we perceive it as such due to certain substances present in this part of the food that were not there in the raw form. Otherwise, we could eat these things raw.

But how is it possible that something that wasn’t there before cooking suddenly appears?

It’s thanks to the Maillard reaction, a process that many are unaware of but one that we all leverage almost every day in our kitchens. Understanding it means being able to utilize it better and create tastier dishes next time.

The basics of the Maillard reaction

To grasp how certain compounds can be present only after cooking and not before, you need to have some basic understanding of chemistry—very, very simple basics (so don’t be intimidated).

If I have compound A and compound B that have the ability to bind, and I put them together, they will do so: at the end of the reaction, I won’t have compound A or compound B anymore—I’ll have only compound A+B, which could be entirely different. A straightforward example is hydrogen (A) and oxygen (B): combining them gives water, the compound A+B. I no longer have pure oxygen or pure hydrogen but a new compound.

Now, the Maillard reaction is somewhat similar, but much, much more complex. So complex that even chemists don’t fully understand it yet.

While it’s fundamentally the same for all foods exposed to high temperatures, it varies for each, and this is where the complexity lies.

An incredibly complex phenomenon

In the Maillard reaction, sugars and proteins bind together, thanks to the energy supplied by heat, forming new substances that we perceive as “good.” Both components are essential for this process: if either sugars or proteins are missing, the reaction doesn’t occur, resulting in something different—think of caramel (sugars only) or pure proteins like chicken breast, which is low in sugars, and consequently, the exterior quickly becomes tough.

In the case of plant-based foods, they typically contain an ample amount of both these components, facilitating the Maillard reaction. For meat, this may not be the case; there could be plenty of proteins and few sugars. That’s why meat is often marinated with lemon, wine, or honey—foods rich in sugars—enhancing the flavor as the reaction is activated.

It goes without saying that in boiling, the Maillard reaction doesn’t take place: when water is introduced between proteins and sugars, they won’t bind. On the other hand, oil infiltrates less, making frying an ideal environment for the Maillard reaction to occur.

How to Manage the Maillard Reaction

Have you grasped what the Maillard reaction is? I know it’s not simple, but if you think I’m making it too complicated, take a look at how Wikipedia explains it—you might lose interest and return here :).

Regardless, the reaction has rules for it to occur properly, and these are theoretical concepts that chefs, those who engage in this every day and have studied for it, are familiar with. Criticisms on Masterchef often stem from contestants having creativity but lacking theoretical knowledge in the kitchen, putting them at a disadvantage.

maillard reaction
Basic explanation of the Maillard chemical reaction in cooking.

At what temperature does the Maillard reaction occur?

The Maillard reaction happens in the range 140°C-180°C / 280°F-360°F. If the temperature isn’t reached, the outer layer will dehydrate, and the food will become tough without browning much, resulting in a lack of flavor.

If it surpasses 180°C or 360°F, it turns black and burnt, and toxic compounds may be released, so it’s better to avoid that.

The crucial aspect of the reaction is that it must be left alone. Firstly, it needs to begin before the proteins and sugars degrade separately. Whether cooking in a pan, on a grill, or in an oven, the temperature must already be high when placing the food inside, or the reaction won’t occur. Once cooking has commenced, things shouldn’t be fiddled with—lifting the meat excessively to flip it or constantly opening the oven will lower the temperature, disrupting the reaction.

When, during cooking, we start to see the color darken, it means the reaction has occurred. The reaction consists of three phases, with the second being the formation of “good” compounds and the third being the browning.

Therefore, only if the color is dark can we conclude that the reaction has taken place, and we can remove the food from the pan or oven.

Of course, this isn’t meant to be a cooking lesson (far from it), just a brief introduction to understanding a complex phenomenon that many witness but may not fully comprehend.

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