Coffee grind size is no small matter. Controlling this variable allows you to improve the taste of your coffee, ensure repeatability, experiment with recipes, and more.
Unfortunately, many a wonderful coffee has been let down by its grind profile. From the wrong size (often caused by a poor understanding of recipes) to inconsistent grinds, there are many factors that can go wrong. The result? Anything from sour or bitter brews to an inability to recreate that perfect cup.
I spoke to Mark Vecchiarelli, Founder of Kruve and the creator of the Kruve Sifter set, endorsed by three-time Japan Barista Champion Miki Suzuki, five-time Canada Barista Champion Ben Put, and more. The tool reduces clumps and ensures grind consistency – so who better than Mark to break down grind size for me?
Brewing pour over coffee: a delicate balance of grind size, brew time, and more.
Grind Size, Extraction, & Flavor
When making coffee, our biggest goal is to achieve a controlled extraction. The final coffee flavor will depend on how many compounds are extracted from those roasted beans into our brew – something that is a delicate balance of water:coffee ratio, brew time, water temperature, grind size, and more.
SEE ALSO: Brew Guide: What Are The 3 Phases of Drip Coffee Brewing?
The whole purpose of grinding our coffee beans is to increase the surface area coming into contact with water. And the finer or coarser the grind, the more or less quickly water can pass through it – affecting brew time as well as extraction efficiency.
A coarser grind has looser particles which, in turn, will allow water to move between them more quickly. The combination of less surface area and a shorter brew time (unless it’s immersion brewing) means that less extraction will be taking place. On the other hand, a finer grind has particles that are packed closer together. This means water takes longer to pass through the grinds and that there’s more surface area – leading to greater extraction.
Is your coffee mouth-puckeringly sour? Your grind size is too coarse – go finer. And if it’s a bitter brew? You have the opposite issue; try grinding coarser.
But there are several factors that help determine the exact grind size that’s best. Let’s take a look at them.
The life of a roasted coffee bean.
What Affects The Ideal Grind Size?
First of all, personal preferences will always determine the ideal coffee recipe. So too will the coffee you’re brewing: depending on the origin, variety, processing method, roast profile, and more, you may want to highlight different characteristics. Dark roasts, for example, are more soluble and so you might use a slightly coarser grind.
However, two points deserve special mention. The first is brewing method: different brewing devices are suited to different grind sizes. A French press, for example, is typically paired with a coarse grind. Most pour overs (one exception being the Chemex) lend themselves to medium-fine grinds. With espresso or Turkish coffee, you’ll want to go fine and extra-fine respectively. And some brewers, like the AeroPress, can suit a wide range of grind sizes.
SEE ALSO:Brewing Methods Compared: How Should You Make Coffee at Home?
Then there’s the age of your coffee. Hopefully, you’ll always have fresh beans to hand but, as the days pass since they were roasted, you’ll want to tweak the brew recipe. This is because the coffee’s flavors will fade over time. In this case, many home brewers and baristas like to grind finer; others prefer to up the coffee dosage and grind coarser to compensate. The first option will increase extraction; the second, intensity.
Yet even while controlling grind size opens up the door to manipulating coffee extraction – and therefore coffee flavor – there are also several things that can make it difficult for baristas and home brewers to do so.
Brewed coffee grounds. Credit: Sam Koh
Coffee Grind Issues: How Big Is Table Salt?
One stumbling block is the vocabulary we use to talk about grind size. How many times have you read a brew recipe that calls for a grind size of “table salt,” “kosher sea salt,” or “fine sand?”
The problem is that many people read these descriptions and don’t actually know what size kosher sea salt is. Even if they do, this is a far cry from any sort of precision measurement. So, this can make replicating recipes or calibrating grinders extremely difficult.
In order to ensure consistent grind sizes, we need a universal language. Sometimes, you can refer to the settings on your grinder. The Baratza Sette 30, for example, uses numbers 1–30. This option isn’t possible with all grinders, however. For many hand grinders, you simply adjust the grind by twisting an unmarked cog – meaning you can’t communicate which ‘setting’ you’ve used.
Different coffee grinders, different scales.
What’s more, since burrs and blades dull over time, two grinders of the same model can still grind differently. In fact, the same grinder may produce different-sized grounds from one season to the next.
And of course, if you wish to use a recipe from someone with a different brand of grinder, “setting 10” will be no help at all.
The team at Kruve prefer to use microns (μm) to measure grind. Their sieves range from 200 to 1,600 μm. Mark tells me that “microns provide the ultimate reference and control”, allowing users to easily share recipes, experiment with different grind sizes, and also calibrate grinders across different shops.
Kruve have produced 15 sieves, available for purchase individually or in sets, meaning users can refine coffee grinds to 105 different micron ranges. Credit: Kruve
The Coffee Grind Consistency Issue
Moreover, no matter what grinder you use, inconsistency can be an issue. If your ground coffee contains a mixture of larger and smaller grinds (“boulders” and “fines,” respectively), these will extract at different rates.
Typically, the larger particles will under-extract while the smaller ones will over-extract. This can result in unpredictable extraction rates, muddle the flavor of your coffee, prevent you from successfully replicating a recipe, and more.
To resolve this, most coffee aficionados opt for high-quality burr grinders – but even the most expensive of these can have a degree of grind inconsistency. Beans tend to shatter rather than neatly cracking. This will nearly always lead to some fines and boulders.
Mark explains that, when Kruve first began designing their grind refining system, they researched how common a problem grind inconsistency actually was. They tried using different sieves, ranging from kitchen to laboratory standard, to sift grinds. The result? Grind particle size varied by up to 1,000% – making consistency an almost-impossible objective.
This is why they set out to offer control to home users, regardless of the grinder or the brew method; Mark compares sifting grinds to using a scale for brew ratio. And they’re not the only ones who believe in the importance of sifting: several Champion Brewers and Baristas have been landing podium finishes using the Kruve Sifter set.
A Kruve Sifter set separates fines (top) and boulders (bottom) from otherwise consistently ground coffee. Credit: Kruve
In the pursuit of high-quality specialty coffee, no variable is too small to consider. By getting the right, consistent grind size, you can craft brew recipes to your exact preferences. You can experiment with different variables. And you enjoy a delicious cup of coffee – not just once, but every single time.
Please note: This article has been sponsored by Kruve.
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Start with a medium-fine grind, and adjust it based on your preferences. For example, if your brew turns out sour (under extracted), use a finer grind next time, and/or increase your brew time slightly. If your brew ends up bitter (over extracted), use a coarser grind next time and/or decrease your brew time.How do you adjust coffee grind size based on taste? ›
If your coffee tastes watery and acidic, you may be grinding your beans too coarsely. Try a finer grind, and see if that fixes the issue. If your coffee tastes overly bitter, you may be grinding too finely. A coarser grind may improve your brew.How does grind size affect coffee flavor? ›
Coffee is affected by how quickly water can extract flavor compounds from your grounds and by the duration of the brewing. Coarser, larger coffee grounds have less surface area than those that are finely ground. They allow water to flow more freely and they do not give up their flavor as quickly.What are the different grind size? ›
There are two different types of grind size: fine and coarse. You can extract the flavor faster from finer grounds, since there's more surface area to extract from.Why does coffee grind size matter? ›
If the contact time is too high or the grind is too fine, it will result in an over-extracted brew which can be bitter. If the grind is too coarse or the contact time is too short, the coffee will turn out weak. Finding the proper balance between the two will help in producing the best cup of coffee possible.How do you adjust grind size? ›
Adjusting the Grind
Only move the dial in very small increments of about three millimetres. If you've been monitoring your grind setting regularly, you'll only ever need small adjustments. A three millimetre movement should change your shot time by three to five seconds, using the same dose and tamp technique.
For regular brewed coffee (in a drip coffee maker) the suggested ratio is two scoops (2 tablespoons) of grounds to one cup (6 ounces) of water. To make your coffee taste stronger add more grounds.What grind size makes strong coffee? ›
Buying whole bean coffee opens many doors to strong coffee because you can grind it as coarse or as fine as you like. We prefer a finer-than-usual grind to ensure maximum flavor. The finer the grind, the more flavor, but this doesn't always work for a brew method that doesn't catch fine pieces, such as a French press.What is the best coffee ratio? ›
A general guideline is called the "Golden Ratio" - one to two tablespoons of ground coffee for every six ounces of water. This can be adjusted to suit individual taste preferences. Check the cup lines or indicators on your specific brewer to see how they actually measure.What are the 4 enemies of coffee? ›
Your beans' greatest enemies are air, moisture, heat, and light. To preserve your beans' fresh roasted flavor as long as possible, store them in an opaque, air-tight container at room temperature. Coffee beans can be beautiful, but avoid clear canisters which will allow light to compromise the taste of your coffee.
There are 4 types of coffee bean. Arabica, Robusta, Excelsa and Liberica. All four have radically different taste profiles.What factors affect coffee Flavours? ›
Four of the main influences on taste include environment, processing, roasting, and brewing. The simplified coffee journey from seed to cup. Each element will have an impact on flavor.What does grind size mean? ›
Your cheat sheet for every coffee brewing process.
Today, we're going over one of the most important and easy-to-adjust brewing method variable: the grind. To start at square one (or, more aptly, irregularly and inconsistently sized particle one): grind size refers to how big or small the individual coffee grounds are.
The processing method makes a difference to flavor and aroma because the sugars in the pulp left on natural or honey processed beans undergo metabolic changes that signiﬁcantly alter the chemical composition of the green beans. These reactions create sweetness and body in the final cup.How can you determine if the grind is correct? ›
Basically, the finer the grind, the shorter the contact time with the water. The grind and the contact time with the water therefore influence each other. If the grind is too fine, the coffee quickly becomes bitter and strong. If the grind is too coarse, the coffee tastes rather sour and watery.What is a medium grind size? ›
A medium grind is slightly finer than table salt or close to dry sand. THINK: Aeropress, Siphon, Flat-bottom (Kalita Wave) or Cone-shaped (Hario V60) brewers.What is the best grind for filter coffee? ›
Choose a medium-coarse grind
The best grind size for automatic drip coffee is a medium-coarse grind. Grinds that are more coarse will be under-extracted, leaving you with a disappointingly weak cup of coffee, while grinds that are too fine will be over-extracted and bitter.
For pour over coffee, the best grind to use is a medium-coarse grind. A medium-coarse grind will be similar in size to a French press grind but less chunky and will feel slightly smoother. If you are using a cone-shaped pour over, then use a medium-fine coffee grind instead.When should I adjust grind size? ›
If you dose and tamp and the coffee in the basket looks the way it should but the shot runs too quickly or too slowly, then you need to adjust the grind size. When changing the grind size, be sure to move in small increments of about three millimetres.Does a finer grind make coffee stronger? ›
The more finely ground the beans, the more caffeine is released into the water. So it's safe to say that when it comes to caffeination, a finer grind does result in stronger coffee, while a coarser grind will always brew a weaker cup.
Grinds too fine can settle and pack together in the basket of the espresso machine, clogging an otherwise even mesh and stymieing water's journey through. As a result, some cups end up bitter, while others end up sour; a few taste strong, a few taste weak.What is the most popular coffee grind? ›
A medium grind is likely the most common grind setting, as it works well in most standard drip pots like Mr. Coffee or Bunn. The medium-fine grind seems to be popular for the pour over cone brewing method.What grind is best for strong coffee? ›
Buying whole bean coffee opens many doors to strong coffee because you can grind it as coarse or as fine as you like. We prefer a finer-than-usual grind to ensure maximum flavor. The finer the grind, the more flavor, but this doesn't always work for a brew method that doesn't catch fine pieces, such as a French press.What grind setting is medium? ›
Medium: A medium grind setting is what many coffee shops will use for a regular cup of drip coffee. Its consistency is very similar to sea salt. Medium Fine: The medium fine grind size is a happy medium between the sizes needed for drip coffee and espresso. Most people will use this size for a pour over coffee.How do I know if my grind is too fine? ›
If the grind is too fine, the flow might not start for 5-6 seconds. The extraction will continue well past 30 seconds. The crema will be dark and might have large bubbles and dark streaks in it. The brew will taste bitter.What angle should you grind at? ›
For surface grinding, use the flat part of the wheel, maintaining a 20°-30° angle between the tool and the work surface.What grind makes coffee less bitter? ›
It has to work its way in. So, if you have larger coffee grounds, there's more work for your water to do, and therefore your coffee will break down slower. That's why, if your coffee is tasting too bitter, you might just want coarser, larger grind particles.
A strong coffee is made by using a higher coffee to water ratio and refers to the concentration of the beverage rather than roast level. Espresso by definition is a strong drink since it's brewed as a very concentrated form of coffee.Does how you grind your coffee make a difference? ›
Getting your grind size right is important. It is a key factor for brewing coffee, no matter the method. Get it wrong, and your cup will end up being over- or underextracted – and you'll be able to taste it.How long should coffee rest before grinding? ›
You may want to start grinding your coffee beans and brewing them within ten to fourteen days after roasting. It's important to let your coffee sit for ten to fourteen days after roasting. During the earlier days after roasting, the beans are rapidly degassing (releasing carbon dioxide gases).
These results are in line with what might be expected: grinding the same coffee twice produces more fines, necessitating a coarser grind setting to get the same shot time, and lowering extraction — supposedly because of increased channelling. However, the taste results didn't match this picture at all.Does coffee lose flavor after grinding? ›
Pre-ground coffee - Once you grind your coffee beans, start the countdown! Ground coffee starts to lose its aromatic and flavor intensity after 30 minutes. The quick loss of aromatics is why you should avoid buying pre-ground coffee as much as possible.