How do you get the flavor of coffee? What is Maynard's reaction in baking?

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Mena reaction (Maillard reaction), also known as Maillard reaction, Maillard reaction and carbonylamine reaction, is a non-enzymatic browning reaction widely distributed in the food industry, which refers to a series of complex reactions between reducing sugars (carbohydrates) and amino acids / proteins in food at room temperature or heating, resulting in the formation of brown-black macromolecular substance melanin or melanin. In addition to producing melanoidin, hundreds of intermediate molecules with different odors, including reducing ketones, aldehydes and heterocyclic compounds, are produced in the reaction process, which provide delicious flavor and attractive color for food.

Mena reaction was carried out by French chemist Louis. Camilla Mena discovered in 1912 that in 1953 John Hodge and others formally named this reaction the Mena reaction. In 1912, Mena told other scientists at the French Academy of Sciences about the yellowish-brown color produced by heating an aqueous solution of amino acids and sugars, but few of those present at the time realized the potential significance of the reaction. Today, Mena reaction has become a technology closely related to the modern food industry, which can be seen everywhere in meat processing, food storage, essence production, traditional Chinese medicine research and other fields. Current studies have also shown that it is closely related to the physiological and pathological processes of the body.

Mena reaction (Maillard reaction) is the most complex chemical reaction in the process of coffee roasting. It is also one of the most important reactions that make coffee have multiple flavors.

During coffee roasting, the Mena reaction mainly begins when the bean color changes to yellow and then brown after dehydration, and the reaction will not stop until you finish baking and until the beans are completely cooled. But at the beginning of the explosion, another reaction that plays an important role in the flavor of coffee: the caramelization reaction will also begin, and it will share the same raw material as the Mena reaction: sugar, which will cause the explosion to begin around. The rate of Mena's reaction began to slow. Therefore, the main Mena reaction stage refers to the period from the beginning of yellowing to the explosion of coffee beans in the roasting process. Melanin, a macromolecular compound, is continuously produced during the reaction, and eventually more than 600 volatile organic compounds are found in roasted coffee beans. So the Mena reaction brings a variety of flavor, taste, color and complexity to the coffee.

In that case, in the process of coffee roasting, we can adjust the degree of Mena reaction indirectly by adjusting the rhythm of roasting (baking curve), and then adjust the flavor of coffee. Since increasing the temperature of the Mayna reaction after 80 degrees Celsius has little effect on the reaction rate, it is generally adjusted by prolonging or shortening the reaction time. Prolonging the Mena reaction time will produce more macromolecular melanin, which will give the coffee a thicker taste and a more complex and deeply toned flavor.

On the contrary, the shorter Mena reaction time will get a lighter taste, low complexity and bright tonality. If the Mena reaction time is too long, the tone of the coffee may be too low, the sour texture will be aggravated, it will not be clean, or the mouth will feel "dry" after swallowing. Too short reaction time may make the coffee flavor too green and monotonous or even almost no flavor, similar to the taste of seeds and immature fruit, sharp acidity, too much astringency, and no texture.

With the increase of reaction time, there is a fresh floral and fruity aroma to a lower tonal aroma of flowers and fruits, followed by more nuts, vanilla, cream and caramel, but the aroma of flowers and fruits will begin to weaken. For example, in baking Ethiopian water to wash Yega Chuefei, the curve I set will be baked with the flavors of flowers, green tea, lemon, cream sugar and bergamot. When I extended the Mena reaction for 60 seconds, it became floral, sweet lemon, vanilla, nut, caramel and chocolate. Shortened by 30 seconds, it is lime, flower fragrance, slightly seed-like characteristics, orange peel, bergamot tonality.

This rule may seem simple and easy to understand, but the origin, variety, treatment, size, density and other factors of coffee beans, want to bake their own satisfactory taste can only slowly try, sum up, try again. There is no such thing as the "best baking method" in the world. I just hope that by understanding the baking process, I can help myself take fewer detours.