What is the "Mena reaction" and "caramelization" reaction in the baking process? the shadow of coffee.

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Qianjie coffee briefly talks about the reaction in the baking process. The baking process is roughly divided into three stages, the first two of which can sometimes be merged. The first stage is the beans on the roaster, when the water overflows from the inside of the beans to the surface of the beans, and the coffee beans are dried. There may not be much effect with the eyes at this stage, but the steam from the roaster has the aroma of grass and warm hay. The second stage is followed by moderate baking, and the complex caramelization and Maillard reactions give us a familiar aroma of coffee. Coffee beans in roasting are less dense, drier and more crisp, and the combination of many factors makes them better permeable and easier to dissolve. When the baking is over, the roaster puts down the beans and enters the third stage of cooling and exhaust.

Maillard reaction, or Mena reaction, is a non-enzymatic browning reaction widely existing in food industry proposed by French chemist L.C.Maillard. Maillard reaction is a series of reactions between reducing sugar and protein or amino acid. Maillard reaction occurs when it reaches a certain temperature by thermal catalysis. After a complex reaction process, it will produce brown or even black-brown macromolecular substance melanin or melanin, as well as other substances.

Maillard reaction brings flavor, taste, color and complexity to coffee.

Raw coffee beans contain a certain amount of sucrose, which is the main source of coffee sweetness. During the explosion period, the caramelization reaction occurs. In the process of caramelization, the sugar in coffee beans is dehydrated under heating, resulting in two kinds of substances, one is sugar dehydration polymer, commonly known as caramel or sauce color. Second, the degradation products, mainly some volatile aldehydes and ketones, these substances can continue to condensation, polymerization, to get dark-colored substances.

Caramelization deepens the color of coffee beans and creates aromas such as fruit, caramel and roasted nuts.

Both reactions are common during food baking. when baking bread, it makes the bread golden and fragrant, while when baking coffee beans, it darkens the color and releases more complex flavors.

Understand the reaction of coffee beans during roasting, but also understand that the roasting process is very important. If less than a second, insufficient caramelization, the aroma will be monotonous, lack of layers of flavor, resulting in adverse effects.