The importance of coffee grinder:
The grinder is often overlooked among coffee newcomers! This is a tragic fact! Before discussing these key points, let’s first take a look at the function of the bean grinder. The aroma and deliciousness of coffee are all protected in the coffee beans. If we soak the entire bean in water, the deliciousness located in the center of the coffee bean cannot be released (or rather, very slowly). So the simplest method is to turn the coffee beans into small granular coffee powder and let hot water fully bring out the deliciousness inside the beans. So, can we buy a whole bag of ground powder and take it home to slowly mix? may not! After coffee is ground into powder, its aroma quickly disappears, and the oxidation rate is very fast, which means that the coffee powder you bring home is drinking the oxidized flavor.
So it’s still recommended to buy an electric bean grinder. Just press one button every day and you can go from hell to heaven. Many beginners purchase coffee powder directly from supermarkets for use. But friends with a little common sense will surely know that the shelf life of coffee after roasting is very, very short. It is generally recommended to consume freshly baked beans within one month! Because within a month, the elements in beans that can bring you the ultimate flavor will quickly dissipate. Coffee ground into powder has a faster oxidation rate due to the increased contact area with air. Generally, 15 minutes after grinding is enough to turn the original premium coffee into waste. That’s why there are always merchants advertising freshly ground coffee! Although sometimes those merchants themselves don’t understand why they need to grind it now!
Some friends here may say that as long as it’s freshly ground, it’s fine!? Can I just buy a few dozen yuan spiral slurry grinder and grind it now! In fact, as long as your beans are of good quality and fresh enough, this method is definitely much better than buying coffee powder directly to brew and extract the flavor! But you still waste coffee beans! The spiral slurry type bean cutter (referred to as a bean cutter because it crushes beans by chopping rather than grinding) not only fails to process coffee beans into evenly sized coffee grounds, but also generates a large amount of heat during the chopping process. Coffee powder accelerates the oxidation process when heated. The flavor will also be taken away! In addition, based on the first principle of successful extraction of premium coffee (uniform extraction), the coffee powder particles chopped by the bean cutter can be coarse or fine, which can also lead to the failure of coffee extraction! The most direct is over extraction or under extraction! Insufficient extraction of coffee can cause sourness and numbness, while excessive extraction of coffee can lead to excessive bitterness and burning!
The relationship between the main variables of coffee extraction is that the higher the water temperature, the more bitter and intense the coffee tastes; the lower the water temperature, the more sour the coffee tastes, with a mild and light taste; The finer the powder, the higher the coffee extraction rate, and the coffee tends to be stronger. Conversely, the coarser the powder, the lower the extraction rate, and the coffee tends to be lighter; The longer the overall extraction time, the stronger and more bitter the coffee tends to develop. Conversely, the shorter the extraction time, the lighter and more acidic the coffee tends to be The principle of gold cup extraction is consistent. Assuming the fineness of the ground powder is determined, if the water temperature is increased, the soaking time should be shortened, otherwise the coffee will be over extracted and the overall taste will be bitter. Otherwise, the extraction will be insufficient and the overall taste will be weak; Assuming your water temperature is fixed, the finer the powder, the shorter the extraction time, otherwise the coffee will be over extracted, and vice versa, the extraction will be insufficient. Assuming your soaking time is constant, the finer the powder, the lower the water temperature, otherwise over extraction will occur, and vice versa, under extraction will occur.
If you still don’t understand, a simple example is stir frying sour and spicy shredded potatoes. If the shredded potatoes you cut are some coarse and some fine, then when you stir fry the fine ones and put them on a plate, you will find that the coarse ones are still raw. But if the coarse ones are cooked, the fine ones have already been fried into mashed potatoes! So a good grinder is the first product that excellent baristas consider in the field of specialty coffee, not a coffee machine or other extraction tools! That’s also why high-performance bean grinders are expensive! So, uniformity is the most important performance indicator of a bean grinder.
There are many factors that affect the performance of a bean grinder, such as speed, disc material, blade shape, grinding speed, and so on. To some extent, the importance of the grinder even exceeds that of the coffee making equipment itself. If the equipment is not good, it can still be compensated for through continuous practice and skilled techniques; The quality of the grinding machine is not high, but it is something that even through practice, it is powerless.
Chop type bean grinder
The biggest advantage of this grinder is its affordability. Another advantage is its small size. But I wouldn’t call this type of device a “grinder”, I would call it a “chopping” bean machine. Such grinders are arbitrary and unconscious, so after the coffee beans are chopped haphazardly, the particle size is very uneven, ranging from large to small.
When we brew coffee, some coffee is already ripe (moderately extracted), some is over ripe (over extracted, bitter, astringent, and sharp), and some is not ripe due to the coarse particles, unable to fully contribute all the aroma (plain, without sweetness). So when using such a grinder to chop and brew coffee, there will be flavors that are just right, too strong, and too light, mixed together. So, do you think this cup of coffee will taste good? If you have such a bean chopper at home, please use it to chop spices and peppers, it’s very useful!
Crushing, shredding and crushing type bean grinder
According to the structure of the grinding disc, bean grinders can generally be divided into three categories: flat knives, cone knives, and ghost teeth:
From the perspective of a magnifying glass, the influence of different blade shapes on coffee powder can be observed through grinding, and the structure and shape of the powder ground by different blade shapes are completely different. The influence of particle structure on coffee flavor is also related to whether the extraction is uniform, and has little to do with the extraction rate. Even if the extraction rate is the same, the flavor still varies, which is caused by uneven extraction.
Flat knife: It grinds coffee beans into particles by grinding, so its shape is mainly flat and long in the form of a sheet.
Cone knife: It grinds coffee beans into particles by grinding, so its shape is mainly polygonal block shaped circular.
Ghost tooth: It grinds coffee beans into particles by grinding, so its shape is mainly elliptical.
Ghost tooth grinder
Generally speaking, the bean grinder with ghost tooth grinding disc is only suitable for grinding single coffee, that is, coffee powder with coarser particles. This type of grinder is represented by Japan’s Fuji R220 and Taiwan’s Yang family’s Grand Pegasus 207N, with high-end models including the American grinding master 875 and Fuji’s R440. This type of grinding disc has an excellent balance and thickness compared to flat or conical knives in terms of extracting flavor from single coffee, but the details are not as precise as flat knives. Often, it is the first choice for ordinary coffee enthusiasts for a single grinder! The two bean grinders I recommend below have similar performance! But the price of Fuji is about three times that of Grand Pegasus. However, Fuji is compact in size and finely crafted, making it more suitable to be placed in a corner of the home. The Great Flying Horse is a big business of coarseness, living a silly and rough life, but this image does not affect its good grinding products.
Ghost tooth is actually a blade type developed based on flat knives. The coffee powder particles ground by ghost tooth are closer to circular shape, and the ratio of coarse powder to fine powder is more uniform, so the coffee taste is cleaner, the flavor is more three-dimensional and full, but the machine price is higher.
Flat knife bean grinder
As for flat knives, they are the most widely held in the market. Whether it’s a single product grinder or an Italian style grinder. Whether it’s the top commercial German Mehdi EK43, the mid-range MAZZER MAJOR, or the home designed Ulikar MMG. Flat knife bean grinders are generally positioned clearly, either pure Italian bean grinders represented by Italian brand MAZZER, or single product bean grinders with watches from German brand Mehedi (some models can also be compatible with Italian coffee products). Due to differences in the design of the blade pattern and the adjustment plate, most Italian brand Italian coffee grinders can only grind fine powder suitable for Italian coffee, and are not suitable for coarse powder of single coffee!
When it is necessary to obtain high concentration coffee in a short period of time, a flat knife grinder is a good choice. High concentration will also make the aroma rich, so using a flat knife will make the aroma more pronounced than a cone knife
Cone knife bean grinder
As for the cone knife, it’s a thousand pounds of oil. Except for the top-level MAZZER ROBUR, most other products are compatible with Italian and single items. However, in the world of cone knives, there is a serious two-tier differentiation, either it is a top-level Italian bean grinder worth tens of thousands of yuan, or it is a low-end entry-level product! Home entry-level products are represented by BARATZA ENCORE, and most home grade small cone knives are compatible with both single products and Italian style. However, the quality of the product varies from person to person. Due to its high efficiency and fast grinding speed, a good cone cutter produces a suitable amount of fine powder that can significantly enhance the layering of coffee. Therefore, many top coffee shops choose it as their standard grinder. Cone cutters are favored by the majority of manual bean grinders due to their high grinding efficiency. HARIO 2TB and LIDO2 are both designed with cone cutters. As for how to choose, I really have to try it myself to understand! After all, what suits your taste is the best!
The cone knife grinder is a machine that places a cone knife disc at the bottom and then uses an outer ring knife disc for grinding. When coffee beans fall from above, they will be pulled down by the rotation of the cone knife disc, resulting in grinding action. Cone knives have fast grinding speed, low heat generation, and lower uniformity and accuracy compared to flat knives, resulting in a richer taste of the products. (There is also a saying that the uniformity of the cone cutter is better, but in actual use, I tend to think that the uniformity of the flat cutter of the same level of grinding machine is slightly better. For more details, it may be related to the price.)
The particles ground by the cone knife are polygonal and close to the granular shape, resulting in a longer water absorption path for coffee particles. It takes longer for the interior to come into contact with water, so the soluble substances released by the cone knife particles in the initial stage will be less, and the concentration will not be too high in a short period of time. At the same time, because the shape is granular, even after long-term extraction, the wood absorbs less water, making it less likely to produce impurities and astringency.
The granular coffee powder produced by the conical knife can reduce the contact time between the wood and water. Although the aroma is not as obvious as that of the flat knife, even if the extraction time is extended, the taste is more rounded and complex.
In addition to the key factor of uniformity, the horsepower of the grinder is also important. Due to the trend of premium coffee, coffee beans are usually roasted moderately, so they are relatively hard. If the horsepower is insufficient, they can easily get stuck and cannot be ground. (That’s why we still recommend electric grinders, which can be tiring to grind manually.)
Cleaning of bean grinder
Pay attention to cleanliness. The coffee shop produces a large amount of coffee every day, and the problem of residual powder does not greatly affect the quality of the coffee. However, if you make it at home, especially if you only make one cup in a day or two, the residual powder left after grinding will greatly affect the quality of the next production. Pay attention to drying it in a timely manner when cleaning at the same time. The cleaning method for grinding rice circulating online is not advisable, as the high hardness of rice can cause significant wear and tear on the grinding disc. For newly purchased grinders or those that have not been used for a long time, you can grind a few coffee beans as a cleaning tool first. If you don’t use it for a longer period of time, then open and clean the grinding disc. Please note that some models are easy to open, while others are not. For friends with strong hands-on ability, you can try it. Generally, for household use, you can just put coffee beans and grind them.
Post time: Mar-18-2025