Guest post by Steven Du
The flavor reaction. What makes bread crust brown and tasty? What makes the smell of searing meat so savory and delicious? How can grill marks and black crust on meats supply such a flavor punch?
Three words: the Maillard reaction. This simple reaction creates thousands of flavonoids that impart food with flavors that make us come back for more every time. The essential components of the Maillard reaction are protein and sugars that lead to flavonoids that make food delicious.
Several factors are important for the Maillard reaction, the most important, however, is heat. From what was likely a simple mistake thousands of years ago, humans have continued to refine the relationship between flames and food. . Simple roasting led to an explosion of culinary techniques and a quest to find flavors to satisfy our desires of delicious foods.
The Maillard reaction requires two other important factors though: protein and sugars. To kick-start the reaction, you first need to heat the components to above 300 degrees Fahrenheit, necessary to evaporate the moisture on the surface of the proteins. The temperature is also crucial because the reaction isn't helped along by enzymes.
Advice for a budding chef attempting to make a delicious steak dinner: Salt for 30 minutes prior to release more moisture and dry the steak out.  By drying the meat, the proteins are exposed to higher temperatures earlier enabling the tasty Maillard reaction to take place.
Be careful of an abundance of sugar, though. Too much can lead to caramelization as opposed to a Maillard reaction due to the relative lack of proteins and amino groups. Caramelization leads to a sweet nutty flavor and brown coloring. By contrast, Maillard reactions result in the development of additional flavors with the addition of the amino groups from proteins, creating a multitude of flavonoids and aromas that blend together together to form a sweet or savory dish.
The basic chemistry in this reaction happens between amino acids and reducing sugars. The carbonyl group of the sugar reacts with the amino group of the amino acid and produces water and other intermediates, which undergo multiple rearrangements . These rearrangements can be from the amadori rearrangement to short-chain hydrolitic fission,[[Export Error -- Unsupported HTML: <sup>1 </sup>.]]which leads to deoxyhexodiulose and other aroma, flavor, and color compounds as seen in figure 1. The more we "brown" the item, the more diverse the flavonoids that come out. However, overdoing the reaction can also lead to toxic byproducts, such as those found in black and burnt foods . Melanoidins are common byproducts from the Maillard reaction, which are the browning pigments seen on meats and breads.
From the basic meat we cook on the stove, to the browning of bread, there are a variety of recipes that utilize the complex, yet pleasuring and delectable Maillard reactions to create delicious foods. The Maillard reaction not only shaped the development of food, it also revolutionized how we look at food.