Coffee technology coffee brewing method

According to the contact mode between water and coffee powder, coffee brewing is classified into four categories: "steaming method", "pressurization method", "gravity method" and "leaching method".

If the water passes through the coffee only once, the finished product will contain mainly soluble substances (including caffeine). If the water cycle passes through the coffee powder many times (like a common circulating filter), the less soluble substances in the coffee beans will also enter the finished product, causing the taste to be bitter, so this method is not favored by enthusiasts.

All coffee is made from ground coffee and hot water; when it is done, the coffee is cleaned out. The thickness of the coffee powder required is related to the cooking method chosen.

Proper water temperature is very important. The choice of water temperature is related to cooking utensils, coffee bean species, coffee bean roasting degree, the water temperature is too low, the flavor of coffee beans can not be fully extracted; water temperature is too high, excessive extraction, taste deterioration and often bitter.

The common ratio of coffee powder to water in Western countries is 15,30ml coffee powder (one to two tablespoons): 300ml water (six ounces). Coffee lovers often take the upper limit of this ratio. Please pay attention to make appropriate adjustments according to the thickness of the coffee powder.

Continuous heating destroys the flavor of brewed coffee, and degradation also occurs at room temperature. Therefore, it is often a failure to keep the coffee warm. However, in an anaerobic environment, coffee can be preserved for a long time at room temperature. So you can see coffee in sealed packages on the store shelves.

Nowadays, many electric coffee pots are highly automated, and some even include the function of grinding coffee beans.

Soaking method

Don't be misled by the name. Don't boil the coffee (at least not for too long), or it will be too bitter.

The easiest way is to put the coffee powder in the cup, add hot water, let it cool and sink to the bottom. This is an old method, and it is still used in some parts of Indonesia. Be careful not to eat the coffee at the bottom of the cup. The advantage of this method is that it is simple and the water temperature is just right.

Turkish coffee is an early prescription and is still used in the Middle East, North Africa, East Africa, Turkey, Greece and the Balkans. Ultra-fine coffee powder is boiled with water in a small container, usually seasoned with sugar and cardamom. The espresso in the cup has foam on it and a layer of silted powder underneath.

"Cowboy Coffee" is to boil the minced coffee directly in the pot and drink it. The name implies a stopgap measure under humble conditions; however, some people prefer it. This is their traditional cooking method in Finland and Sweden, where per capita consumption of coffee is the highest.

Pressure method

Espresso is made from 80 to 96 degrees Celsius hot water at a force of 8 to 9 atmospheres through compacted coffee cakes, usually only 30 milliliters per cup. It is one of the strongest of the common coffee, with a unique aroma and a touch of oil (Crema) floating on the surface. It can be drunk alone; it can also be further made into a variety of other drinks. Because of its fast brewing speed, high concentration and low caffeine content, this method is used in many chain coffee shops or seasoned coffee.

The mocha pot, also known as the Italian coffee pot, is a three-layer stove. After boiling water at the bottom, the coffee powder is pushed through the middle layer by steam pressure to enter the upper layer, and the coffee concentration obtained is comparable to that of espresso, but there is no oil slick, but if a pressure reducing gasket is installed at the coffee spill outlet, the golden crema can be extracted. The mocha pot and the semi-automatic espresso machine have the same structure, but the way the water comes out is upside down. Remove the fire from the bottom of the pot as soon as possible after the coffee spills about 30~40cc, and then wipe it on the bottom with a cold towel.

Gravity method

In the American coffee or filter paper method, the minced coffee is placed on a filter paper or metal filter and hot water flows from top to bottom. The concentration of coffee depends on the proportion of water added and the thickness of coffee powder, but it is generally lower than that of espresso.

Electric circulating filters were very common in the United States before the 1970s. It is different from the mocha pot mentioned above: the hot water boils into the top floor, then passes through the coffee scraps from top to bottom and goes back to the heating room; it circulates several times. It is precisely because the hot water passes through the coffee powder many times in this method, this kind of coffee has poor taste.

Leaching method

The French filter Press (French press) is a tall glass cylinder with a piston with a filter. Soak the hot water and coffee powder in a cylinder for four to seven minutes, then press the coffee powder to the bottom by a piston filter, and the top coffee can be poured out to drink. This "complete immersion method" is considered by many experts to be an ideal household method for making coffee.

Coffee bag is a portable package for travel, which is very rare at ordinary times.

Malaysians put coffee powder in cotton pockets, soak them in hot water, and then remove the cloth bags from the hot water. This kind of pocket is the same as using filter paper. This is more suitable for strong local coffee, and the coffee in the bag can be reused.

The vacuum coffee pot (Syphon) is made by connecting a heating container and a funnel container. The connecting part is a filter with coffee dust on it. After boiling in the heating container, the water goes into the funnel container and mixes with the coffee powder; at this time, the heating source is cut off, and the partial vacuum formed by the cooling of the heating container pulls the coffee back to the bottom through the filter.