It is estimated that Americans drink 400 million cups of coffee every day—that’s 146 billionper year! Of this massive number, about 79% of them brew theirs at home. You would think that with such a huge client base, they would know the best possible ways to concoct their homemade cup of joe.
However, this is not always the case. There are so many different ways to prepare coffee, whether you grind up the beans yourself or buy them pre-ground, that it can actually be a bit confusing. Even at places like Starbucks, the long list of coffee varieties can be overwhelming.
In this article, we will not only explore how different coffee grind sizes can affect your favorite hot beverage, but also how to achieve your desired brew. Hopefully, by the end you can become your own personal barista!
Under and Over-Extracted Coffee
So, why is the size of coffee grounds so important? What do the consistency and texture do to affect the flavor? It all comes down to whether you have over-extracted and under-extracted coffee, which is the root of its flavor profile.
Extraction refers to the process of getting all of the soluble flavor from the grounds. This is affected by how coarsely you grind the beans and how long the coffee itself brews. Though there are recommended machines and consistencies to be used based on the type of coffee and how you like your flavors, the extraction philosophy remains constant.
Though it is much more convenient to buy pre-ground coffee, it is important to take into account that once it has been ground, the oxidation process immediately begins. The more oxidized the grinds become, the less fresh and robust your coffee will taste.
Store-bought and pre-ground coffee takes care of the grind size for you, which means that you are not in danger of corrupting it through under or over-extraction yourself. However, it is not as fresh, so the quality and flavors can become less than optimal.
Because of these factors, you are much better off buying whole coffee beans and grinding them yourself to achieve the most superb cup possible.
With all this in mind, let us delve further into the risks of having under and over-extracted coffee and how they are produced.
Under vs. Over-Extracted
Under-extracted coffee is produced when it has not been brewed long enough or the grinds are too coarse. The resulting flavor is described as:
It is also lacking the typical lingering coffee taste, and you know that your coffee is not living up to its full potential.
Over-extracted coffee, on the other hand, is too finely ground. This type is described as having a flavor profile that is:
Sometimes, you cannot even taste the beans. Other times, the flavors are so overpowering that the coffee becomes downright unpleasant to drink.
To rectify under or over-extraction, you can either use a different brewing machine or adjust brewing time to establish the best possible flavors. This brings us to our next topic: what is the best grinder to use for your coffee?
Blade vs. Burr Grinders
The two main categorizations of at-home coffee grinders are blade and burr grinders. Each of these uses different methods to grind up the coffee beans, which affects their consistency and thus, their ending flavors.
Blade grinders are cheaper and more compact than burr grinders. They operate similarly to blenders and food processors in that they use rotating blades to break down the beans into smaller particles. The longer the grinder is on, the more coarse your coffee will become.
Because of the high speed at which blade grinders operate, the grind is often inconsistent or uneven. You have the potential to end up with partially over or under-extracted coffee grounds, which can only end in disaster in terms of flavor.
In fact, many people say that you are better off just buying the pre-ground coffee. Because the blade grinders operate at such a high speed, they generate heat and friction. This added warming process amounts to coffee that does not taste as fresh or robust.
Conversely, burr grinders can be very pricey and very large. They operate at low speeds to produce uniform pressure that crushes the beans and allows for more even consistency. Rather than using blades, burr grinders utilize interlocking discs with sharp teeth that can come in a flat or conical variety.
Flat-style burr grinders are not as good as the conical variety because the structure of it can result in pieces of coffee grinds getting stuck in the machine. If you do not clean this out, it can negatively impact future cups of coffee and you run the risk of cross-contamination.
Conical-style burr grinders, however, are what most professional baristas use—and for good reason. The structure of this type of machine has a chamber that the ground coffee can fall into, eliminating the possibility of grinds getting stuck in the machine.
As an added bonus, with conical burr grinders, you can adjust the distance between the burrs (what are used to grind the beans) to affect the consistency. This makes the machine much more versatile, as different types of coffee are best at different consistencies. The further apart the blades are, the larger grind size you will end up with.
Further Grinder Considerations
The last thing you have to think about when choosing the correct grinder is if you want an automatic/electric or a manual one. Burr grinders are typically manual, while blade grinders tend towards automatic. However, it is up to you to decide which one is best for your needs.
A manual grinder takes longer, but you have much more control over the brewing process. You can watch the coffee beans break down through the grinding process and stop whenever you see that it has reached the desired consistency. Manual grinders are best for single-serve brewing methods, and the end result tends to be more gourmet than if you were to use an automatic.
An automatic grinder will save you loads of time, but you cannot be as particular about grind size. Efficiency is an automatic grinder’s main appeal, as it does most of the work for you. This is a big plus if you are making large amounts of coffee or coffee for multiple people. Another added bonus is that you end up with more consistent grind size.
Now that you have weighed the pros and cons and determined the best grinder to use to make your perfect cup of coffee, let us move on to the specific resulting consistencies and the ideal machines used for them.
Coffee Grind Consistencies
Coffee grind consistencies typically range from extra fine to extra coarse. This depends not only on the type of machine you use, but it is important to consider that certain types of coffee work best with specific consistencies. Ending up with the wrong consistency can result in foul-tasting coffee that leaves an unpleasant aftertaste on your flavor palette.
Now that you have a visual representation, let us delve further into what these sizes mean:
- Extra fine
- Looks like flour
- Used primarily for Turkish coffee
- Looks like powdered sugar
- Used primarily for espresso and Aeropress brewing
- Looks like table salt
- Used primarily for drip coffee brew methods
- Medium coarse
- Looks like coarse sand
- Also used primarily for drip coffee brew methods
- Looks like sea salt
- Primarily used for French Press brewing
- Extra coarse
- Also looks like sea salt
- Primarily used for cold brewing
Consistency in Relation to Surface Area
So, why else does the consistency matter so much? Along with the fundamental under and over-extracted concept, it also has to do with the grind’s surface area—this comes down to a type of science.
When the water is in the process of extracting the flavor particles from the grinds, it does not immediately soak through and permeate the outer coating of the beans. This outer coating must be bypassed to get to the center, which is where the flavor lies.
Thus, when coffee is finely ground, it has a greater exposed surface area. This means that the water does not have to soak through the beans to extract the flavor, as the core’s flavor is already exposed. Sometimes this is okay, like if you are making a cold brew, but for the most part it is not ideal.
Next, let us explore some of the most common brewing methods.
Espresso brewing only takes about 30 seconds, so it’s great for efficiency. However, you may only use extra fine grinds for an espresso machine if you want to achieve the ideal cup. As mentioned before, not grinding them up enough will lead to under-extraction.
Because espresso is such a notoriously strong brew, the less concentrated flavors will effectively destroy its integrity. Too coarse and you will end up with a sour, watery cup, and too fine will result in a bitter flavor and burnt aftertaste.
An Aeropress is a special machine because there is no optimal grind—you have the ability to choose consistency based off of what type of coffee you want. It uses a type of plunger presses the grounds down through a thin paper filter to prevent excess grinds from entering your cup.
Though an Aeropress is a single-serve machine, which can be a bit tedious if you are brewing for more than one person, the timing varies. This depends on grind consistency. The finer it is, the shorter the brewing time—some can take as little as a minute, while others may take a few.
As evidenced by its name, a French Press, like an Aeropress, also uses a plunger-type apparatus to extract a grind’s full flavor. This type of machine works best with coarse or extra coarse blends, but it takes a bit longer than an Aeropress—usually about 3-5 minutes.
You can tell whether your coffee is too finely ground or not based off of the ease at which the plunger goes down. If there is little resistance, the grind is probably too coarse, and if you are struggling to push it down, it is likely too fine.
Unlike an Aeropress, a French Press uses a mesh filter instead of a paper. Though this is more environmentally friendly, it also means that there is a higher chance of sediment seeping through. Another difference is that grinds are steeped in hot water for a few minutes before being pressed.
This type of preparation is unique because there is no hot water involved. Rather, the grinds are steeped at room temperature, which can develop excellent flavors if you have the right consistency.
For this method, an extra coarse grind is usually best, but this hinges on your anticipated brewing time. The longer you intend to steep, the coarser your grounds can be. You have a bit of leeway based off of personal taste, so it is smart to experiment until you find the right one.
If you are short on time, this method is not for you—the steeping process can last between 12 and 24 hours, but the end result is a truly special cup of coffee.
Grind Size by Coffee Brewing Method (Video)
With so many different coffee preparations, it is easy to become overwhelmed with information. The quality of coffee is largely dependent on the size of the coffee grinds themselves, and there are numerous options to achieve your ideal consistency.
The main takeaway from this is that your goal should be to not produce under or over-extracted coffee, no matter what degree of coarseness is required for your chosen brewing method. Because this, again, is dependent on the grind size, it pays off to be attentive during the grinding process.
Whether you choose to go for espresso or cold brew, automatic or manual, and blade or burr, your options are truly infinite!