Coffee roasting knowledge: how much does the weight of cooked coffee beans decrease after roasting?

Weight reduction: 15-20% weight reduction due to evaporation of water

Under this explanation, under normal circumstances, the moisture content of our coffee beans will be 10-12%.

In addition, the weight lost is generally silver, dust, material change, and the loss of carbon dioxide.

Most of the less weight is moisture.

Volume increase: due to the formation of CQ2, the volume increases by 30-60%

Composition proportion change: fat increases by 12-16%, sugar content decreases by 10%, and acid content decreases by 3%.

Check and select the coffee again.

Caffeine: caffeine in coffee beans is an alkali. People with allergies should not consume too much caffeine. Caffeine is soluble in water, so it can be extracted from raw coffee beans in one of the following ways:

1. Water-soluble method: use a cylindrical extractor in which coffee beans are placed and treated with a water-based extraction solution mixed with saturated coffee solubilizer-non-caffeine.

2. Ethyl acetate: ethyl acetate is a solvent that can also be found in nature. Use it to wash raw coffee and extract caffeine.

3. Dichloromethane: dichloromethane is a chemical solvent that volatilizes naturally when the temperature is higher than 40 ℃; it is used to wash raw coffee to extract caffeine.

4. Carbon dioxide: under critical conditions (gas / liquid, pressure = 250bar), carbon dioxide (CQ2) acts as a solvent to wash raw coffee and extract caffeine.

Production process: first put a small fire lamp on the water rack into the siphon coffee pot to grind the coffee beans, put the ground coffee powder into the upper pot as the water temperature rises below, the steam pressure causes the water to rise through the pipe and merge with the coffee powder in the upper pot. After mixing the coffee powder and water evenly with a small stick for a period of time, remove the small fire lamp under the pot to cool the air in the next pot. Vacuum can give the necessary assistance, that is, wrap the next pot with a wet towel to help the kettle cool. At this point, the coffee liquid will return to the bottom pot through the filter cloth, so that the coffee will be cooked.

Coffee has different baking time according to different varieties. What is made from lightly roasted coffee beans is the so-called white coffee. This kind of coffee is less popular and is a Malaysian specialty. At that time, I was curious and bought and drank it online, and it tasted good. The following Mantenin coffee has been roasted for a long time, the color is shiny, and when the beans reach about 400 degrees Fahrenheit, they will turn dark brown. At this time, the coffee beans begin to produce oil, a process called high temperature decomposition, when the roaster has to decide whether to continue baking, timing is very critical, once overroasted, the coffee beans will be destroyed.

A series of chemical changes occur in the process of baking. After about 5-25 minutes of baking (depending on the temperature selected), the green coffee beans lose some humidity and turn yellow. In this process, the coffee beans will swell, changing from a strong, high-density raw bean to a low-density fluffy state. After this process, the coffee beans will about double in size and begin to show a light brown after stir-frying. After this stage is completed (after about 8 minutes of baking), the calories will be reduced. The color of the coffee soon changed to dark. When the preset baking depth is reached, cold air can be used to cool the coffee beans in order to stop the baking process.

Baking is roughly divided into shallow baking (Light), medium baking (Medium), urban baking (City) and deep baking (Deep). Light roasted coffee beans: will have a strong smell, very crisp, high acidity is the main flavor and slightly mellow. Medium-roasted coffee beans: have a strong mellow, but also retain a certain degree of acidity. City-baked coffee beans: the surface is dark brown, the acidity is replaced by slight bitterness, and most of the flavor has been destroyed. Deep-roasted coffee beans: dark brown in color and oily on the surface. For most coffee beans, the alcohol content increases significantly and the acidity decreases. In fact, roasting coffee is a way of processing food. The roasting of professional coffee is the personal expression of the roaster. Just started to contact with professional coffee.

Reduced weight of roasted coffee (how much less weight of cooked coffee beans after roasting) discount on the weight of roasted coffee beans and raw beans.

Source:

Wen Honggang's blog