Effects of grinding methods, particle size and uniformity of coffee beans on coffee grinding degree and taste

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How to judge and set the grinding degree of espresso

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Effects of grinding methods, particle size and evenness of coffee beans on coffee taste 1 one ● introduction the world's three largest beverages are coffee, tea and cola. According to the Taiwan Coffee Association, the total amount of raw and cooked beans imported into Taiwan in 1996 was about 1575 metric tons, and by the end of 2006 it had reached 10654 metric tons, an increase of nearly six times. However, the annual consumption of coffee in China is more than 35 billion yuan, and about 80,85 cups per person per year, which shows that coffee has become a common drink in modern life. Generally speaking, the taste of ground coffee generally contains fragrant, sweet, bitter and sour taste. Besides beans, the grinding style and roasting blending of coffee beans also have a significant impact on the taste of coffee. In particular, the matching between grinding and blending methods is often ignored by most people, so this paper hopes to explore the effects of grinding methods, particle thickness and uniformity on the taste of coffee through the literature. Historical Origin it is said that coffee was discovered by a shepherd named Kaldi in the highlands of Ethiopia. Cody found that his sheep became energetic after eating the fruit of a plant. Cody then distributed the fruit to the monks in the monastery, and all the monks who had eaten it felt refreshed. As a result, this fruit is gradually regarded as a refreshing herb, which is the earliest record of raw coffee history. Arabs were the first people to eat coffee by chewing the whole fruit (Coffee Cherry) without grinding to absorb the juice. Later, they mixed the ground coffee beans with animal fat as a physical supplement for long trips. It was not until 1000 AD that green coffee beans were boiled into drinks in boiling water. In the 13th century, Arabs consumed a large amount of coffee because of the strict prohibition of drinking in the Koran, so "religion" became an important factor in promoting the widespread popularity of coffee in the Arab world. In the fifteenth century, the world's earliest cafes appeared in Estantinople and Damascus, where customers often came to drink caffeine, play chess, and play cards. In the 16th century, coffee was gradually introduced into Europe through Venice and the port of Marseilles in the name of "Arabian wine". The custom of drinking coffee in Europe was slowly spread by Italian Venice merchants in business in the 17th century, and Bottegadel, the first coffee shop in Europe, appeared in Venice. Decades later, coffee shop signs were put up one after another in London, Paris and Vienna, and then gradually spread around the world because of the outward expansion of Europe and other powerful countries. So far, cafes are everywhere! 2. Taste of coffee beans the taste of a good cup of coffee should be sour, sweet and thick, and a good coffee should have a rich taste, in which the source of aroma, sweetness and bitterness is 5% of the sugar in raw coffee beans. After baking at high temperature, the sugar is blackened by coking and converted into caramel, which can bring unique aroma and bitterness to the coffee. The rest of the sugar will leave some sweetness. The acidity of the fruit mainly comes from the natural acid extracted from the fruit, but some of the poor sour taste is because the beans contain tannin, which will produce pyrosylic acid after boiling, making the coffee taste sour.

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Effects of grinding methods, particle size and uniformity of coffee beans on coffee taste 23. Coffee beans seem ordinary, but they are used in the cultivation, production and roasting of coffee beans. All have their own importance, and grinding is important because the brewing method must be matched with proper grinding to make delicious coffee. Generally speaking, the way coffee is brewed determines the size of the particles to be ground. The shorter the coffee is brewed, the more surface area and water contact the coffee powder has to expand, and the finer the particles are needed; on the contrary, the longer the brewing time, the rougher the grinding particles must be. In other words, the longer the extraction time, the thicker the coffee beans will be ground, so as not to cause excessive extraction and all the bitter taste will come out; the shorter the extraction time, the finer the coffee beans will be ground, so as to avoid insufficient extraction. Therefore, if you want to make a good cup of coffee, you must first understand the characteristics of different blending methods in order to determine the thickness of coffee powder grinding. The following are several common brewing methods: 1. Paper filter dripping this method uses the principle of filtration to fully integrate water and coffee powder through filter paper, and then slowly drip it into the cup, and then brew the coffee which feels mellow and smooth. In order to prevent the coffee powder from affecting the taste through the filter paper, and the blending time is longer, so when using this method to make coffee, it is suitable to use coarse ground coffee powder. 2. Siphon this method uses the principle of physical siphon to form a closed system through the vacuum tube between the two containers. The water is boiled to produce vapor pressure, and the water rises through the tube to the upper container to mix with the coffee powder. After several minutes, the fire source is removed. Due to the effect of the temperature drop in the lower layer, the coffee liquid is pumped from the upper layer to the lower container. After filtering, the taste is light and refreshing. And the cooking process takes a long time. Because the mixing time is shorter than the filter type, it is suitable to match the coffee powder in grinding. 3. Pressure this method is to brew coffee by making hot water quickly penetrate the coffee powder under high pressure. it can be divided into French and Italian: A. the tool of French steam pressure method is simpler than siphon method, and it is more convenient and fast to brew and brew. The principle of punching and adjusting is to use the principle of stamping. Coffee powder and boiling water are put into the barrel-shaped French steam pressurized coffee pot. After the coffee powder is fully absorbed and expanded, the action of filtering and extraction is carried out through the filter screen. Because the filter screen can not filter out the oil, so the taste is stronger than other blending methods. In order to avoid insufficient extraction, the taste is too light, so match the coffee powder in the grinding. B, Italian steam pressurized type uses the principle of high pressure, boiling hot water through the tube through the coffee powder, from the bottom up or from top to bottom, brewing fragrant, mellow and bitter Italian coffee. Espresso in Italian means haste, so that the coffee powder can be instantly

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The effect of the grinding method of coffee beans, the thickness and uniformity of particles on the taste of coffee is characterized by brewing coffee with a strong flavor. Because the brewing time is the shortest, this method is suitable for the use of finely ground coffee powder to avoid insufficient extraction and light taste. The following table shows the difference between French steam pressurized coffee brewing method and Italian steam pressurized coffee brewing method: table 1 the difference between French steam pressurized coffee brewing method and Italian steam pressurized coffee brewing method shows that French steam pressurized Italian steam pressurized brewing principle requires shorter (longer) adjustment time for high pressure principle. (shorter) the particle thickness of coffee powder must be matched with each method of brewing. The time required is also different. Table 2 individual comparison of different blending methods: table 2 individual comparison of different brewing methods time coffee powder grinding thickness suitable reason paper filter dripping type long thick so that the coffee can be fully infiltrated to release aroma, so a rough degree of grinding is required. The most abundant way to keep coffee flavor is siphon type, water drop type and French steam pressurized type, which can not be done by machines and other methods. After the coffee bean powder is fully mixed with hot water, the aroma of the coffee is precipitated. Filter the fat, protein and bad impurities in the coffee to get a refreshing coffee, enjoy the delicious taste and take into account the health at the same time. Water drop type, Espresso Italian steam pressurized type short and fine under the set pressure, the coffee is released in the way of bubbles, the coffee brewed has a steady thick and fragrant flavor, and the beans have to be ground fine enough to give full play to the effect of high pressure extraction. To sum up, when making coffee, you must aim at the method of making coffee and match it with appropriate grinding particles in order to make a delicious cup of coffee. If the blending time is long but with fine grinding, the coffee will taste bitter, on the contrary, if it is matched with coarse ground coffee for a short time, the taste will be very light, so the two must be matched correctly. Fourth, the introduction of the bean grinder determines that the key to the particle thickness and uniformity of coffee lies in the choice of the bean grinder. The following introduces the characteristics of different bean grinders. The function of the bean grinder is to grind the coffee beans. a good bean grinder adjusts the appropriate grinding coefficient and produces uniform coffee powder particles, and does not produce grinding heat to make the coffee powder bitter and astringent, resulting in the loss of coffee flavor. therefore, the bean grinder is also the key to determine whether the coffee is delicious or not.

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Effect of grinding method, particle size and uniformity on coffee taste 41. Characteristics of excellent grinder: A. the so-called grinding coefficient refers to the thickness of coffee powder. if the coffee powder does not make a proper combination of thickness and fineness, it will lead to uneven extraction and inconsistent extraction time, resulting in over-extraction and bitterness. Or cause insufficient extraction, the taste is too light, so the impact of grinding coefficient on the quality of coffee can not be ignored. B, the temperature produced during grinding should be lower and the temperature of the grinder is too high, which will make the coffee powder bitter and astringent, resulting in the loss of coffee flavor. C. the uneven size of the uniform particles of the ground coffee powder will lead to the inability to grasp the brewing time and make the taste inconsistent. When grinding coffee, in addition to the thickness of the grains, the uniformity will also have a serious impact on the taste, because the coarse and fine particles release the coffee flavor at different times, so if the grinding is not uniform, the accurate extraction time cannot be controlled. so that the coffee has an inconsistent taste, the taste is not so pure. 2. Types of bean grinders generally common coffee grinders can be divided into the following three categories. The following will be compared according to the differences in grinding coefficient, grinding heat and particle uniformity: A. hand bean grinder (Hand Crank Coffee Mill) this kind of bean grinder has a variety of shapes, classical flavor, is very suitable for collection, the lowest price, small size, the fun of grinding beans, because hand-shaking, it is difficult to produce grinding heat. It is also unable to adjust the grinding coefficient, and the grinding is not uniform, so it is more suitable for paper filtering and dripping brewing. B, serrated bean grinder (Burr Mills) this kind of bean grinder has scale instruction, and it is not easy to produce high temperature because of the rapid grinding, but it usually has a higher price and more stable uniform grinding, so all kinds of cooking methods are suitable. Most of the people who use this kind of bean grinder are located in higher-end cafes. C, propeller type bean grinder (Blade grinders) this kind of bean grinder uses blade oars to grind roasted coffee beans into coffee powder, the price is lower than the sawtooth type bean grinder, the disadvantage is that it is easy to produce high temperature after high-speed friction, there is no way to correctly grind the coffee powder of uniform size and there is no scale display, it is just convenient to use. PDF created with pdfFactory trial version www.pdffactory.com

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The effects of the grinding method of coffee beans, the thickness and uniformity of particles on the taste of coffee 5 most of the coffee beans used at home are small electric grinding propeller bean grinders, this kind of grinding machine can not grind coffee beans evenly, so it is necessary to rotate as gently as possible to avoid friction and make the beans lose fragrance. In order to have a good cup of coffee, don't ignore the importance of grinding every time you taste the coffee. The following table compares the characteristics of three kinds of coffee grinder: table 3 comparison of the characteristics of coffee grinder grinding coefficient grinding hot particle uniformity hand-operated bean mill X saw tooth type bean mill X "X" propeller bean grinder X reference ● conclusion: to make a cup of coffee with good taste and aroma You should have the correct knowledge of the coffee brewing method and the size of the grinding particles. To sum up, different cooking methods need to be matched with suitable particles, and the cooking time is also different, long time should be matched with rough grinding, short time should be matched with fine grinding, so as not to affect the taste, therefore, rough grinding is suitable for paper filter drop type, medium grinding is suitable for siphon type, water drop type, French steam pressure type, fine grinding is suitable for Espresso Italian type, steam pressure type, in addition. The key to determining the diameter and uniformity of coffee particles lies in the bean grinder. A good bean grinder adjusts the appropriate grinding coefficient to produce uniform coffee powder particles, and will not produce grinding heat to make coffee powder bitter and astringent. There are so many matching relationships to pay attention to, if you really know how to avoid these mines, you can also make delicious coffee.

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