The change and degree of roasting process the flavor characteristics of roasting degree of coffee beans on the comparison table

The five stages of baking:

1. Dry, when the raw bean is heated, the water vapor in the raw bean will evaporate, and when it reaches about 135 degrees, the raw bean begins to lighten from green and gradually whitens.

two。 Dehydration, as heating, raw beans from green to light yellow, when the temperature is about 160 degrees, will emit the smell of grass, or the aroma of baked grain, continuous heating, beans will turn light brown.

3. An explosion, after about 190 degrees dehydration is completed, the cell wall ruptures due to internal thermal expansion to form an explosion. At this time, a series of thermal decomposition reactions do not occur in the beans, in which the caramelization reaction will bring the sweetness, dark brown and mellowness of the coffee beans. the explosion lasts about a minute.

4. The second explosion, as the heating goes on, enters the second explosion, at which time a more violent reaction will take place inside the beans, giving off a lot of heat. With the end of the second explosion, the raw bean has basically blackened, the bean body has expanded to about 1.5 times that of the original, the surface is oily, and the weight is reduced by about 12% and 20%.

5. Stop baking, usually no later than one minute after the end of the second explosion, when the temperature reaches 230, it will be a deeper French or Italian baking, when the temperature is higher than 230 degrees and then continue to heat the coffee beans may scorch naturally.

Criteria for dividing the degree of baking:

1. The roasting degree of coffee beans is generally divided into: shallow baking, medium baking, deep baking, heavy baking.

two。 Each category can be subdivided into two categories, a total of eight:

Shallow baking: Light,Cinema

Medium baking: Medium,High

Deep baking: City,Full-city

Re-bake: French,Italy

As the temperature, heat and other small changes in the baking process may change the taste of coffee beans, different beans have different characteristics and baking is a work completed in a short time within 10-20 minutes, so bakers are required to master the relevant principles, clearly grasp the characteristics of raw beans, and in the baking process, accurate budget, timely adjustment. In fact, because of the complexity and variability of the baking process, a real baker needs not only theory, but also a lot of experience and perception.

Source: happy Coffee Xiao Xu's blog