How to correctly control the grinding degree and extraction time of coffee beans

When adjusting the degree of grinding, it is necessary to consider the contact time, extraction rate and flow rate in advance. When looking for reasons why coffee is too bitter or too weak, check whether the coffee powder is ground properly.

Making coffee is an art, the choice of coffee beans, the grinding degree of coffee powder, and even the use of what kind of water quality is also very particular, this may be the charm of coffee, carefully cook a cup of strong coffee, slowly taste, certainly do not have a taste. Simply put, the finer the ground coffee, the slower the flow of water. The slower the flow rate, the longer the extraction process and the more fully the coffee flavor is extracted. In addition, water usually flows out along the path of less resistance, so the uniformity and uniformity of grinding are crucial. If the grinding is uneven, the distribution of water flow will be uneven, resulting in uneven extraction. Water flow is also an important basis for you to judge whether the degree of grinding is appropriate. If the flow rate is too fast, it means that your coffee powder is too coarse, and the coffee taste will be too flat; but if the flow rate is too slow, or there is sediment at the bottom of the cup, it means that your coffee powder is too fine, the coffee taste is too heavy, and the taste is too bitter. In addition, the contact time is closely related to the extraction rate of coffee. It sounds complicated, but it's really simple to understand. Extraction rate, i.e. the total amount of soluble matter extracted from coffee by water. If the extraction is insufficient and the soluble substance content is too low, the coffee will become very sour or lack sweetness. If scientifically explained, acids and salts dissolve faster than sugar, coffee lacks sweetness because sugar in coffee has not had time to dissolve, and excessive extraction can bring burnt taste to coffee. Only by controlling the grinding degree and contact time correctly, you can get the ideal extraction rate and the coffee will become more delicious. Contact time is the total time that water and coffee powder are in contact. For example, French coffee and espresso coffee have a very different contact time. If the contact time between water and coffee powder is long, your coffee powder needs to be ground coarser; if the contact time is long, the coffee powder is ground very fine, and your coffee will definitely be over-extracted, losing aroma and leaving only bitter taste. And vice versa, if contact time is short and coffee grounds are ground very coarsely, your coffee will become bland and tasteless. Find the right balance between grind and contact time, and you'll make a truly good coffee. At the same time, different brewing methods have corresponding grinding degrees. The degree of grinding affects coffee taste in three main ways: contact time between coffee powder and water, extraction rate and water flow rate. Where does a cup of strong coffee come from? High quality coffee beans are the first element, and the degree of grinding of coffee powder is equally important. The degree of grinding of coffee powder can greatly change the taste of coffee. If the coffee is slightly different, the taste will become bitter or the taste will become silky.