Do you have to understand the chemical reaction in coffee roasting? the change of coffee beans in the boiler

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Chemical reactions aside, the physical changes of coffee beans during heating are already quite complex: the same bean, fried in the same way (that is, the same roasting curve), may not taste the same. Some enthusiasts like to stick graphs on their bags when communicating. Although this helps testers understand the basic information about the baking period, it is almost impossible to copy the taste by chart alone: when learning to stir-fry beans, the author likes to try to stir-fry coffee in the same producing area with the curve recommended by others on the Internet, but the results vary, and many expected flavors do not appear. One reason is that the figures reflected by the thermometer do not represent the real situation: like hot water in a water pot, the bottom is hotter than the top. And the location of the thermometer, each brand of fried bean machine is different. Even if it is the same model, professional bakers will make adjustments before using it.

Assuming that the thermometer is accurate, it only measures the surface temperature between beans. It's like a giant oven full of chickens of different sizes. The figures on the display screen do not reflect the deepest temperature of the chicken.

Unlike boiling water, coffee beans go through two "endothermic and exothermic" (endothermic-exothermic) stages during heating: when the beans are still emerald green and have a high water content, the heat is first absorbed and evaporated by the water, and the temperature rises slowly. On the contrary, coffee beans will release heat during the first explosion (as is the case with the second explosion). If you do not try to lower the temperature in the furnace, the beans will be fried quickly. Phosphorus vomiting