There are black residues in the coffee that cannot be dissolved. This is Luckin Coffee’s response. Why are the prices different in different stores? Uncover the reasons and solutions behind this.

Black coffee grounds: what they are and where they come from

When enjoying a cup of hot coffee, you may find black grounds on the bottom or wall of the cup. Many people may wonder: What are these black particles? In fact, these black grounds are mainly coffee residues that have not been completely dissolved by coffee powder or have not been completely filtered out during the brewing process. They usually appear in small particles with irregular shapes and usually do not affect the taste of coffee, but if they appear frequently, it may be a sign of improper brewing method or improper use of utensils.

The black grounds in coffee are mainly composed of the undissolved part of the coffee powder. These coffee powders are not completely dissolved by water during the brewing process. This may be because the grinding is too coarse or the water temperature is too low, resulting in the coffee powder particles not being able to fully release their flavor and oil. In addition, these black grounds may sometimes be due to incomplete filtration of filter paper or improper filter design, resulting in unfiltered coffee powder mixed into the liquid.

The source of black grounds may also be related to the quality and processing of coffee beans. Low-quality coffee beans usually contain more impurities and insoluble parts, which also increases the possibility of grounds residue in the Luckin Coffee app. During the processing, the degree of roasting of coffee beans will also affect the formation of grounds: over-roasted coffee beans may produce more fine particles, affecting the filtering effect of coffee.

Coffee powder selection and grind size: how it affects the dissolution of grounds

The choice of coffee powder and the degree of grinding are two key factors that affect the taste of coffee and the appearance of grounds. If the selected coffee powder particles are too large or too coarse, the contact area between the coffee powder and the water will be reduced during brewing, resulting in the inability to fully release the dissolved substances in the coffee, and finally leaving undissolved black grounds. This phenomenon is particularly common when using a French press or drip coffee machine.

The coarseness of the grinding directly affects the extraction effect of coffee. When coarse coffee powder is soaked in water, the dissolution process is slow and the extraction is insufficient, resulting in the inability to completely dissolve the oil and solid matter in the coffee, thus forming precipitation. Such coarse particles not only affect the taste, but may also cause more residue to accumulate at the bottom of the cup, affecting the clarity of the coffee and the smoothness of the taste.

To avoid this phenomenon, it is recommended to choose the appropriate grinding size according to different brewing methods. For example, when using an espresso machine, you should choose a finer coffee powder to ensure that the water flow can quickly and evenly pass through the powder to complete full extraction; while a French press pot requires a slightly coarser grinding size to avoid too much dissolution of the grounds and cause the taste to be too strong.

In addition, the choice of coffee powder should not be ignored. Fresh coffee beans usually contain more oils. Too coarse grinding may make these oils difficult to dissolve, resulting in residues remaining in the coffee liquid. Therefore, fine grinding and reasonable selection of coffee beans are the key to ensuring a clear coffee taste and no residues.

Water temperature and brewing method: key factors in avoiding residue problems

Water temperature and brewing method are two important factors in the coffee brewing process, which directly affect the solubility of coffee powder and the extraction effect. If the water temperature is too low, the coffee powder will not dissolve completely, resulting in more undissolved particles and grounds remaining in the coffee. Especially when using a drip coffee machine or hand brewing, too low water temperature may cause the coffee flavor to be incompletely released, resulting in bitter or uneven tasting coffee.

The ideal water temperature should be between 90°C and 96°C. Below this temperature, the coffee is not fully extracted, the oils and dissolved substances in the coffee powder cannot be fully released, and it is easy to leave insoluble black residues. If the water temperature is too high, it may be over-extracted, resulting in a strong and bitter coffee taste, and it may also accelerate the precipitation of residues.

In addition, improper brewing methods can also affect the dissolution of grounds. When using a French press, if the water temperature is too low, the coffee powder may not release enough flavor and cause too much undissolved solid matter to accumulate. When using hand-brewed coffee, the speed and method of pouring water are also crucial. If the water flow is too fast or too slow, it may lead to uneven extraction, resulting in more grounds.

To solve these problems, first make sure to use the right water temperature, which can be precisely controlled with a temperature-controlled kettle. Secondly, during the brewing process, keep the water flow steady and avoid pouring water directly into the center of the coffee powder accumulation. Try to make it evenly soaked so that the coffee powder can be evenly extracted and reduce insoluble particles.

Utensil Use and Cleaning: Key Factors Affecting Coffee Grounds Disposal

Different coffee machines have different ways of handling coffee grounds during use. For example, coffee machines that use filter paper can effectively filter out most of the coffee grounds, ensuring the clarity of the coffee and the smoothness of the taste; while machines such as French presses and espresso machines tend to retain more grounds because they use pressure extraction and coarse filter designs, which can cause some larger coffee particles to not be completely filtered out.

However, even the most sophisticated coffee equipment can cause black grounds in your coffee if it is not used properly or cleaned regularly. Long-term use of uncleaned equipment may accumulate old coffee grounds and grease, which will mix with fresh coffee powder, affecting the extraction effect and may cause additional grounds to remain. Especially for sealed coffee pots, if they are not cleaned in time, the grease and coffee grounds inside will affect the brewing quality.

In addition, overuse or long periods of uncleaning of coffee equipment will not only affect the taste of the coffee, but may also make the filter or filter paper less effective, resulting in an inability to effectively filter out the coffee grounds. For example, if the mesh filter in a French press is not cleaned in time, it may clog some holes, preventing the coffee grounds from passing through smoothly, thus affecting the clarity of the coffee.

To avoid these problems, it is recommended to clean the coffee utensils thoroughly regularly, especially the metal filters and filters. They should be washed with warm water after each use and ensure that they are completely dry before storage. At the same time, choosing the right coffee utensils and filtering methods can also effectively reduce the problem of grounds and improve the overall quality of coffee.

Practical tips for avoiding coffee grounds: for the perfect taste

To avoid black grounds in coffee, you first need to choose the right coffee powder and adjust the grinding degree. Too coarse or too fine coffee powder will affect the extraction effect of coffee, resulting in the grounds not being completely dissolved. For drip coffee machines or hand-brewed coffee, it is recommended to use coffee powder with a medium grinding degree, which can ensure sufficient extraction and avoid too many grounds.

Controlling the water temperature is also a key factor in avoiding grounds. Water temperature that is too low will cause the coffee powder to not dissolve fully, leaving undissolved particles; while water temperature that is too high may cause over-extraction, produce bitterness and increase the precipitation of grounds. The ideal water temperature should be maintained between 90°C and 96°C to ensure that the coffee powder can release its flavor in the best condition.

In addition, properly cleaning coffee utensils is also an important part of avoiding coffee grounds. If coffee utensils that have been used for a long time are not cleaned in time, old coffee grounds and grease will accumulate, affecting the effect of the next round of coffee brewing. Especially for utensils with high pressure such as French presses and espressos, the filter net or filter paper should be cleaned regularly to ensure that the filtering effect is not affected.

Finally, choosing high-quality coffee beans can also effectively reduce the production of grounds. High-quality coffee beans are usually more uniform and less likely to leave too many impurities and undissolved particles. Therefore, choosing freshly roasted coffee beans and ensuring that they are properly stored will provide you with a clearer, ground-free coffee experience.

Avoid Brewing Mistakes: The Right Way to Ensure Quality Coffee

In the daily coffee brewing process, many people often make some common mistakes, which will directly affect the taste and quality of the coffee. A common mistake is to use too much coffee powder. Although increasing the amount of coffee powder can increase the concentration, too much coffee powder will cause uneven coffee extraction, resulting in bitterness or too many grounds. The correct way is to adjust the ratio of coffee powder to water according to the brewing method. Generally speaking, the ratio of drip coffee machines is 1:15, and the ratio of espresso is about 1:2.

Another common mistake is using water that is too hot. Many people are used to brewing coffee with boiling water, but in fact, too high a water temperature will cause the coffee to be over-extracted, producing too much bitterness and undissolved particles. The ideal water temperature should be between 90°C and 96°C, which can ensure that the flavor of the coffee is fully released while avoiding unnecessary grounds and bitterness.

In addition, many coffee lovers neglect to control the water flow when brewing. For example, when using hand-brewed coffee, if the water is poured too fast or too slow, it may lead to uneven extraction and affect the taste of the coffee. The correct way is to pour water at a slow and even speed to ensure that the water flow evenly covers the coffee powder, which can effectively avoid excessive grounds and maintain the delicate flavor of the coffee.

In general, mastering the correct coffee brewing method can not only help avoid common mistakes, but also improve the overall quality of coffee. Choosing the right coffee powder, controlling the appropriate water temperature and pouring method are all key factors to ensure that every cup of coffee can show the best flavor.

Creating the perfect cup of coffee: a comprehensive solution to your grounds problem

To ensure that every cup of coffee is free of black grounds, you first need to identify the common reasons why coffee grounds cannot be dissolved. First, the choice and grinding size of coffee powder are key. Too coarse or uneven coffee powder will lead to incomplete coffee extraction, leaving a lot of grounds. The solution is to choose the right grinding size, usually medium grinding size is best for drip coffee machines and hand brewed coffee.

Secondly, water temperature and brewing method are also key factors affecting the grounds. Water temperature that is too low will result in insufficient dissolution of the coffee powder, while water temperature that is too high will result in over-extraction and produce more insoluble particles. The ideal water temperature should be maintained between 90°C and 96°C to ensure that the flavor of the coffee can be fully released. In addition, keep the water flow even when pouring water, and avoid pouring water too fast or too slow to ensure that the coffee powder can be evenly extracted.

Cleaning and maintaining coffee utensils is also very important. Long-term use of uncleaned utensils will cause old grounds and oils to accumulate, which will not only affect the taste of the coffee, but also prevent the grounds of the new coffee from being completely filtered. Therefore, regular cleaning of coffee utensils, especially the filter and filter paper, can effectively reduce the residue of grounds and ensure that every cup of coffee is clear and transparent.

Finally, choosing high-quality coffee beans is also an important factor in ensuring perfect coffee. High-quality coffee beans contain fewer impurities and insoluble substances, which can effectively reduce the production of grounds. Combined with the appropriate amount of coffee powder, water temperature, brewing method and cleaning of utensils, you will be able to brew perfect coffee without black grounds.