Some terms related to extraction
Extraction: the word extraction comes from Latin, which means to squeeze something or get an extract. In chemistry, extraction refers to obtaining valuable substances (flavors) from raw materials (coffee beans). There are many kinds of extraction methods, the most common one is to extract the flavor of coffee powder with hot water, and brewing is also often used instead of extraction.
Excessive extraction: refers to the contact time between coffee powder and hot water is too long, or the ratio of coffee powder to water is too low. When using drip coffee machine and brewed espresso, excessive grinding will lead to excessive extraction. When cooking by hand, the extraction time may be too long. Excessive water temperature can also lead to excessive extraction. Excessive extraction will extract too many unnecessary chemicals, such as caffeine, which will make coffee taste bitter and unbalanced.
Extraction time: The contact time between coffee powder and water is an important variable of good coffee. Other terms such as brewing time or soaking time also refer to extraction time.
Powder-water ratio: the ratio of coffee powder to water. In order to achieve the best flavor balance, every gram of coffee powder and every milliliter of water are very important.
Some terms related to coffee beans
Wang Na Cherry: The fruit of coffee tree, named after its red causal skin and similar shape to cherry.
? Round beans: During the growth of coffee cherries, one of a pair of seeds inside developed very well, and the other seed was eaten, which made the coffee beans that should be round round round.
Ivory beans: larger than ordinary coffee beans, usually dull in taste.
Coffee belt: usually refers to the area between the Tropic of Cancer and the south, because this area is most suitable for growing coffee.
Drying method: the method of separating coffee pulp from seeds and obtaining raw beans by sun exposure.
Water washing: a method of separating coffee pulp from seeds by water treatment to obtain raw beans.
Semi-water washing method: the first half is dried in the sun, and the second half is washed with water, so that the coffee slurry is separated from the seeds to obtain raw beans.
Boutique coffee: also known as "specialty coffee" and "selected coffee". It refers to coffee made from raw beans that grow in a few extremely ideal geographical environments and have excellent taste characteristics. According to the special soil and climate conditions in which they grow, they have outstanding flavor. After strict selection and classification, this kind of coffee is considered as a selected coffee bean because of its hard texture, rich taste and excellent flavor.
Pica coffee variety: Coffee variety, the only coffee product with 44 chromosomes, is the most important variety in the coffee market at present.
Robusta Coffee Variety: A coffee variety with high yield, easy care and poor quality, which is mainly used to make instant coffee. Robusta is the main variety in the market after Arabica.
Silver skin: a thin film on the surface of raw beans, which usually falls off when baking.
First explosion: With the progress of baking, the temperature of beans began to rise. As a result, the ingredients in coffee beans began to undergo various chemical changes, and the color, bitterness, acidity and aroma of coffee beans were also formed bit by bit. At this time, water vapor and carbon dioxide are gradually produced in coffee beans, which increase the pressure inside the coffee beans, so the coffee beans expand. Because the card can't bear more and more pressure, with the crackling sound, the cells of coffee beans are destroyed, which is the so-called "primary explosion"
Second explosion: After the first explosion, some components produced during heating began to decompose. In this process, gas will be produced, which will make the beans expand continuously. With the expansion of coffee beans, cells are destroyed once, and then cracks occur, which is called "secondary explosion".
Non-gaseous reaction: the reaction in which coffee beans continue to emit carbon dioxide after roasting.
Dehydration: generally speaking, it refers to the baking process below 170 degrees. Different baking utensils need different dehydration time, but it is generally controlled within 5~8 minutes, depending on the water content of beans.
Bar temperature: usually the crawling speed of baking is controlled between 7~ 14 degrees, which is related to the control of firepower. The optimal crawling speed is controlled around 10 degree, and the crawling speed of beans with different water content is different. Hard beans and in-season beans (with high water content) should crawl slowly to prolong the dehydration time, while soft beans or old beans (with low water content) should crawl quickly to shorten the dehydration time to preserve the flavor of beans.
No smoke: baked beans began to smoke at 180 degrees, and the smoke increased after the first explosion. The deeper the second explosion, the greater the smoke emission. At this time, the air door should be fully opened to avoid the attachment of flue gas from baked beans.
Slippery: This is what most baking beginners ask. In fact, sliding means cooling down or turning off the fire, and continuing to bake beans with the temperature of the boiler.
Raising beans: don't drink coffee beans immediately after drying, and keep them for a few days to complete the exhaust reaction, so that the flavor of coffee beans is fully mature.
Defective beans: raw beans with broken, abnormal or moth-eaten appearance.
About coffee utensils
Propeller-type bean grinder: The grinding tip of the bean grinder is similar to a propeller.
Disc grinder: a machine that grinds beans with a flat knife.
Cone mill: a bean mill with a cone-shaped grinding edge.
Bean trough: the space above the bean mill for storing coffee beans.
Bean jar: the place under the bean grinder where the ground coffee powder is placed. Bean bins are usually allocators of business models.
Weighing device: a tool for quantifying coffee powder, usually used in combination with the bean trough of a bean mill.
Declining plate: a small part attached to some mocha pots, mainly to let users put less coffee powder.
Relief valve: a valve used to release the pressure in the mocha pot, which will open when the pressure reaches the set pressure.
Pressure storage valve: A valve designed to store pressure in a mocha pot. Its structure is the same as the pressure relief valve, but its function is different.
Flannel: a kind of flannel material, which refers to filtering coffee powder in brewed coffee with flannel.
Way.
Metal strainer: a brewing method in which coffee powder is filtered by extremely fine-pore metal.
Others:
Oxidation: substances react with oxygen to form new compounds.
Caramelization: Chemical reaction during coffee roasting. Also called Mena reaction, it is a chemical change at high temperature. Although there is the word "coke", it has nothing to do with the combustion phenomenon.
Channel effect: Because water is inert, it will choose the path with the least resistance when passing through coffee powder.
Espresso: A way of brewing coffee with high-pressure hot water.
Stuffy steaming: When brewing coffee with a filter, water is first injected into the coffee powder, and then water injection is suspended, so as to extract more coffee flavor by prolonging the contact time between the coffee powder and water.
Mocha: Mocha may represent three meanings, namely, the name of 1 coffee, a pot for brewing coffee, and chocolate flavored coffee.
Atmospheric pressure: the pressure exerted by air on an object on the ground level. The atmospheric pressure of one square centimeter on the earth is one kilogram, also called 1Bar.
Kelima: A kind of milk white material floating on the surface of espresso is the essence of espresso.
Flower pulling: When milk bubbles are poured into espresso, a beautiful leaf pattern is formed on the coffee through the change of wrist.
Barista: Italian name for a professional barista.