General knowledge of boutique coffee about coffee bean grinding

Concepts and principles of coffee grinding:

The operation of crushing roasted coffee beans is called grinding. The props used to grind coffee beans are called grinders.

The ideal time to grind coffee is to grind it before cooking. Because ground coffee is easy to oxidize and lose its flavor, especially without proper storage, coffee powder is also easy to change flavor, so it is naturally impossible to cook mellow coffee.

Some people are afraid of trouble or do not want to buy more bean grinders, so they usually buy ready-made coffee powder when they drink coffee at home. At this time, they should pay special attention to the problem of storage. Because the climate in Taiwan is humid, it is best not to place coffee powder at room temperature at will. A more appropriate way is to put it in a sealed jar and refrigerate it in the refrigerator, and do not put it in the same place with garlic, fish and shrimp and other heavy-flavored food. Because the coffee powder is easy to absorb, a careless coffee becomes a strange taste coffee, then even the best quality coffee will be spoiled. However, some people put the cooked coffee powder in the refrigerator as a deodorant, which is a good way to make the best use of things.

When grinding beans, the size of the powder depends on the way it is cooked. Generally speaking, the shorter the cooking time, the finer the ground powder; the longer the cooking time, the thicker the ground powder. In terms of actual cooking, the ESPRESSO machine takes a very short time to make coffee, so the grinding is the finest, and the coffee powder is as fine as flour; it takes more than a minute to cook coffee by blocking the air, and the coffee powder is medium-sized grinding; American filter coffee takes a long time to make, so the coffee powder is the thickest, like Beijing grains on a shell beach. Grinding coffee powder with appropriate thickness is very important for making a good cup of coffee, because the extraction of water-soluble substances in coffee powder has its ideal time, if the powder is very fine and cooked for a long time, resulting in over-extraction, the coffee may be very bitter and lose its aroma. On the other hand, if the powder is coarse and cooked too fast, resulting in insufficient extraction, the coffee will be tasteless because it is too late to dissolve the water-soluble substance in the powder.

Generally speaking, a good grinding method should include the following four basic principles:

1. The degree of grinding suitable for brewing and cooking should be selected.

2. The temperature of cattle produced during grinding should be low.

3. The powder particles after grinding should be uniform.

4. Grind before cooking.

No matter what kind of grinder is used, it is bound to generate heat by friction in operation. Most of the fine substances are highly volatile, the heat of grinding will increase the speed of volatilization, and mellow is lost in the air.

After the coffee bean is ground, the cell wall will completely disintegrate, the area of contact with air will increase a lot, the rate of oxidation and deterioration will become faster, and the coffee will lose its flavor within 30 seconds to 2 minutes. Therefore, it is recommended not to buy coffee powder, it is best to buy coffee beans, grinding before drinking, grinding should be brewed as soon as possible.

Before the invention of the bean grinder, people used stone pestles and bowls to grind coffee beans. A doctor abroad once experimented with this ancient tool and compared it with a modern bean grinder. It is said that the coffee powder made from pestles and stone bowls is the most mellow.

According to logical reasoning, the pestle cracked the coffee bean naturally by impact, which should not destroy the cell wall and retain the excellent substance of coffee. However, in modern life, it is almost impossible for people to use pestles and stone bowls to grind coffee beans, so choose good ones.