Initial processing and roasting of coffee

Because all coffee cherries don't ripen at the same time, you need to go back to the same tree many times to pick. Coffee beans come from a mature seed called coffee cherry (cherries), which is named because of its bright red color. Generally speaking, coffee beans can be processed in two ways: washing (wet method) and drying (dry or unwashed method).

Washing type (wet method)

Remove the pulp from the outer layer of the coffee cherry and soak it in a large cement tank filled with water. After fermentation, the water-washed coffee will have a distinctive and clear flavor. The fermented coffee beans are washed with clean water, then removed from the water and dried in the sun or machine. Finally, the peel and silver peel are removed by a sheller, which can be screened and divided into different grades of raw coffee beans.

Drying (dry method)

The treatment is to spread the coffee cherries widely on the exposure field for two weeks and sweep them with a rake several times a day so that the coffee beans can be dried more evenly. When dried, the coffee beans are separated from the skin, and the dried pulp and peel are removed by a sheller, then screened and divided into different grades.

Both washing and drying can produce the best quality coffee. Generally speaking, water-washed coffee has distinct acidity and consistent flavor, while dry coffee has lower acidity and more varied flavor. Colombia, Kenya, Costa Rica, Guatemala, Mexico, and Hawaii all use water washing methods. Most of the coffee produced in countries including Brazil, Ethiopia and Indonesia is dried, but some water-washed coffee is also produced.

The selection and grading of coffee depends on the particle size and concentration of beans, as well as the number of defective beans in a pound (broken beans under ripe beans, etc.). Like the best wine, the careful handling and selection of professional coffee in the production process can be seen in the quality of the beans, because the product will have a unique representation, which represents the origin, climate and growers.

Before grinding coffee beans, the processing is roughly divided into the following steps:

First, peeling: the peel and most of the pulp are removed mechanically.

Second, fermentation

Third, drying

Fourth, roasting: through roasting, raw coffee beans can release the special aroma of coffee. Each coffee bean contains its fragrance, sour taste, sweetness and bitterness. How to release it incisively and vividly depends on the heat of its baking. From the insipid raw beans to the endless aftertaste in the cup, roasting is a very important step in the long journey of each coffee bean. Coffee beans are about 10 or 20 minutes long (inversely proportional to the temperature) and the temperature is as high as more than 200 degrees Celsius. In the process of dialogue with the hot dish, coffee beans undergo many chemical changes, giving off a first explosion, a second explosion, a sound like popcorn, and loss of moisture. From raw beans, light and medium roasting to deep roasting, moisture is released again and again, the weight is reduced, but the volume expands and bulges, the color of coffee beans deepens, the fragrant oil is gradually released, and the texture becomes crisp. In raw beans, there is a lot of chloric acid, which gradually disappears with the baking process, releasing familiar and pleasant fruit acids such as acetic acid, citric acid and malic acid in wine. Baking is just right to present these beautiful sour flavors.

Light baking-when the beans make the first light sound, the volume expands at the same time, and the color changes to a delicious cinnamon color. Acidity dominates the flavor of shallow roasted beans, texture and taste have not been brought into full play, generally used as canned coffee.

Medium roasted-coffee beans show an elegant brown color. This method of baking is also called city roast. Medium roasting can not only preserve the original flavor of coffee beans, but also moderately release aroma, so the blue mountains of Jamaica, Colombia, Brazil and other individual coffee, more choose this roasting method. At 20 minutes, the oil begins to surface, and the beans are burned into an oily dark brown, called full-city roast, when the sour, sweet and bitter taste of coffee reaches the perfect balance, and the character of coffee beans is clearly depicted.

Deep roasting-the darker the color of the coffee beans, the sweeter the flavor, when the oil has turned into caramel, bitter back to sweet, endless aftertaste, the most suitable for the strong Italian Espresso, so it is also called Italian baking. Moderate roasting gives life to the coffee beans and turns them into intriguing sweetness and bitterness. People who are sensitive to caffeine might as well choose deep-roasted beans, because in the process of deep-roasting, caffeine will slowly escape, so the deeper the roasted beans, the lower the caffeine content, the caffeine content in a cup of Espresso is only half that of other medium-roasted coffee, the general Espresso coffee has less capacity, and the caffeine content is much higher if it is equal to the capacity of ordinary coffee.

It should be noted that the roasting of coffee beans is divided into primary roasting and secondary roasting. The difference depends on the size of the coffee shop. Due to resource constraints, small coffee shops have only one machine, which requires the entire roasting process to be completed at once, while for larger coffee shops, there will be at least two machines that can work together to complete the baking process in two stages. After two times of baking, the acidity of the coffee beans is greatly reduced, and the aroma is clear, sweet and refreshing.