In this post I’ll explain how to grind coffee beans both with and without a grinder, as well as discuss some of the finer points of coffee grinding:
- Difference between blade and burr grinders
- Difference between flat and conical burr grinders
- The 7 different grind sizes
- The importance of grind consistency
- How long ground coffee lasts
- What makes espresso espresso?
Comment below to let me know your favorite coffee grinder, any non-traditional grinding methods you love or any great coffee recipes in your repertoire!
Table of Contents
- 1 How to Grind Coffee Beans With a Grinder
- 2 How to Grind Coffee Beans Without a Grinder
- 3 Which Grind Method Should You Choose?
- 4 How Much Ground Coffee Per Cup?
- 5 How Long Does Ground Coffee Last?
- 6 Can You Store Coffee in the Freezer?
- 7 Coffee Bean Grind vs Espresso Bean Grind: What’s the Difference?
How to Grind Coffee Beans With a Grinder
There are 2 ways to grind coffee beans with a grinder:
- Blade grinder
- Burr grinder
Let’s review each.
A blade grinder is similar to a food processor or blender, looking like a propeller with a rotating axis in the middle and blades shooting outward.
Essentially, blade grinders spin really quickly and your coffee beans into tiny bits.
This significantly reduces the quality of the grind because the resulting ground coffee isn’t consistent in size.
Some of the particles will be a fine, powdery dust. Others will be large chunks.
Plus, the high speed required to smash the coffee beans generates heat, which can leach away flavorful organic compounds and decrease the quality of the resulting coffee.
Why would anyone choose a blade grinder? They tend to be cheaper.
If you’re shopping for a coffee grinder, it’s burr or nothing, baby!
OK that’s not entirely true for everyone, but it is for me. I use a manual burr grinder and I love it.
A burr grinder functions by placing two rough, burred plates in close proximity and truly grinding the beans as they fall between the plates. You can adjust the gap between the two burred plates, which allows you to control the coarseness of your grind.
The result is a very consistent grind size.
Below are images of my Culinary Prestige Manual Burr Grinder, which I absolutely love.
The black knob on the bottom attaches to the screw in the middle, allowing me to tighten or loosen it to adjust my grind size.
As you can see, the design of this burr grinder ensures my coffee is ground consistently to the same level of coarseness.
Once the grounds are small enough to pass through the gap, they fall into a collection compartment (not shown in these pictures).
There are two different choices you’ll have to make when purchasing a burr grinder:
- Electric vs manual
- Flat vs conical
Mine above is a manual, conical burr grinder.
Which one is right for you? It depends on your preferences. Here are some of the benefits of each grinder type.
Electric vs Manual Burr Grinder
This choice is pretty simple and comes down to cost vs convenience.
Flat vs Conical Burr Grinder
Let’s take a look at the modes of action for flat vs conical burr grinders, courtesy of FreshCup.com:
This makes it seem like conical burr grinders are the no-doubt winners, but flat burr grinders have the most important factor in their favor: consistent grind size.
For more information about burr grinders, this YouTube video is a great resource.
Best Burr Grinder
- Metallic flat burr grinder for coffee lovers
- Burr mill system avoids overheating, preserves aroma and has grind fineness selector for a precise grinding
- 9 grind levels: From fine (espresso) to coarse (french press) to perfectly grind every type of coffee beverage
- 8 oz. Clear bean container; quantity selector from 2 to 12 cups to grind the exact quantity you need
- For safety, if the bean container and/or the lid is not properly in place to active the micro switches, the grinder will not operate
How to Grind Coffee Beans Without a Grinder
OK, so you don’t have a grinder handy.
How will you get your fix?!
Try these 7 different methods:
- Blender or food processor
- Mortar and pestle
- Frying pan
- Rolling pin
- Ask your local coffee shop
Blender or Food Processor
This is the beginning of the coffee grinding options that I’ll politely term “less than ideal.”
Similar in style to a blade coffee grinder, you can use a blender or food processor to pound your coffee beans into submission.
However, I find it’s much, much harder to get anything better than a choppy medium grind by grinding your coffee beans this way.
Begin by adding a small amount of beans, blending on the “grind” setting. Adjust the speed until you get something resembling your desired grind size.
Mortar and Pestle
Much more classic looking than just about anything on this list, you could also grind your coffee with a mortar and pestle.
It’ll be difficult to achieve a consistent grind any larger than dust, but that makes this a
great intriguing option for anyone trying to achieve a coffee bean powder for a Turkish coffee.
Just be prepared for it to take practically forever, and keeping beans from jumping out of the mortar bowl as you crush them probably will be annoying.
It’s better to use a ceramic set because it’ll be more resistant to the coffee’s oils.
We’re now leaving the realm of anything that could remotely be considered grinding.
Now we’re hammering.
Follow these steps:
- Put your coffee beans inside a plastic bag, preferably something tougher like a freezer bag
- Optional but encouraged: cover the bag with a thin towel to prevent the hammer from tearing the bag
- Hammer away
A meat tenderizing mallet or anything with a large, flat, blunt head works best, but I suppose you can use any type of hammer-like object.
You won’t get a fine grind for an espresso, but it would work decently well for a French press grind.
Using the same logic — and process — as the hammer, you can use a frying pan to achieve your grind.
Not any frying pan will do, though. You’re going to want something with a little weight to throw around. If you’ve got a cast iron frying pan laying around, that’ll get the job done.
Sticking with the “put coffee in a plastic bag and crush it” theme, you could also use a rolling pin.
When all else fails, you’ve probably got a knife lying around, right?
No, I’m not suggesting you chop your coffee beans up into the grind size you want.
Instead, look for a butcher-style knife with a tall blade and use the flat side of the knife to crush your whole bean coffee.
It’s similar to how you’d crush a fresh clove of garlic.
Ask Your Local Coffee Shop
Starbucks won’t do this but if there’s a non-corporate local coffee shop in your neighborhood, you could try bringing your beans and asking them for a favor.
Just make sure you’re really nice to the barista. Tip them a buck or two!
Pro Tip: Work some sad sap details into your story. Maybe your significant other just left you and took the coffee grinder, leaving you without the most important part of your life.
(By which I mean the coffee grinder.)
If you’ve got a better story, comment below. I want to hear it!
Which Grind Method Should You Choose?
I’ve had times where I’m in a pinch and just need ground coffee of any kind, but generally you’ll want to choose a method of grinding with two factors in mind:
- Grind size
The 7 Different Coffee Grind Sizes
Below are the 7 different grind sizes and the type of coffee to which they’re best suited:
|Grind Size||Description||Use For:|
|Extra Coarse||The biggest grind possible on your brewer and comparable to ground peppercorns||Cold brew coffee, cowboy coffee|
|Coarse||About the size of heavy kosher salt with visible chunks||French press, percolator, cupping|
|Medium-Coarse||Similar to coarse beach sand||Chemex, conical drip coffee makers, clever dripper|
|Medium||Similar to typical beach sand||Conical pour-over brewers, flat-bottomed drip brewers, Aeropress|
|Medium-Fine||About as fine as table salt with smaller grains than you'd expect to find on a beach||Conical pour-over brewers, Aeropress|
|Fine||A little finer than table salt, this is the grind you likely received if you've ever purchased pre-ground coffee||Espresso, stovetop espresso makers, Aeropress|
|Extra Fine||Similar to flour or powdered sugar, you probably need a special grinder to achieve something this fine||Turkish coffee|
Two notes about this table:
- Aeropress finds itself in 3 categories: medium, medium-fine and fine. If you wish to use a fine grind with an Aeropress you should allow for a 1 minute extraction time. If you use a medium grind try a 3 minute extraction time.
- Without a coffee grinder you won’t be able to achieve better than a medium-coarse grind, and that’s probably with significant effort. Give cowboy coffee a try!
The following image from Batdorf & Bronson Coffee Roasters is a great visual representation of the above table.
How Important Is Grind Size?
Grind size is vitally important to the quality of your coffee. Small changes to grind size (and consistency, noted below) can drastically affect the taste of your coffee due to 3 factors:
- Extraction rate
- Flow rate
- Required contact time
The table below shows how each factor is correlated with grind size:
|Grind Size||Extraction Rate||Flow Rate||Required Contact Time|
Coarser grinds have less surface area and require more contact time with water. However, they also allow water to flow between the grains much more quickly, shown above with the higher flow rate.
Note that “Contact Time” can have 2 meanings:
- Required Contact Time: How much time is needed for contact between grounds and water
- Drip Contact Time: With drip brewers, how much contact time will actually be observed between grounds and water due to water dripping on and passing through the grounds
Because of the higher flow rate with coarse ground coffee, you need more contact time. However, the higher flow rate reduces the observed contact time in drip brewers as water flows much more freely through the coarser grounds. The inverse is true for finer grinds.
Grind quality is so important that for most home baristas looking for a low- or medium-cost startup, the vast majority of their costs should be allocated to a proper grinder.
Keep it Consistent
In the coarser vs finer table above we discussed how grind size impacts your coffee. One such variable was extraction rate.
When you brew coffee you’re trying to extract the best combination of compounds to yield a balanced, caffeinated brew. The following awesome graph by theconversation.com via LifeHacker shows the extraction rate of different compounds over time.
When mixing coffee grounds and hot water you’re trying to extract the proper amounts of volatile oils and organic acids to produce your ideal cup of coffee. Your goal:
- Extract long enough to get enough of the flavorful volatile oils
- But not so long that you extract too many of the bitter organic acids
If your contact time is off you’ll either overextract or underextract your grounds. What does each taste like?
- Overextracted coffee: Bitter, dry, hollow
- Underextracted coffee: Sour, salty, watery
For optimal extraction you want to mix your coffee grounds with water for the proper period of time, and each coffee grind size has its own optimal contact time (which is also dependent upon water temperature).
This is why grind consistency is so important.
Example: Importance of Grind Size Consistency
Imagine you’re brewing coffee with 2 batches of grounds.
- Batch 1: 100% medium-fine grind
- Batch 2: 50% medium grind, 50% fine grind
Batch 1 has grinds all of the same size, so we know the contact time for a great cup of coffee: 2 minutes with my Aeropress, including both bloom and plunging.
Batch 2 has grinds of 2 different sizes, each of which has a different optimal contact time:
- 50% medium grind requires 3 minutes of contact time
- 50% fine grind requires 1 minute of contact time
We have a little bit of a dilemma here, don’t we? By my estimation we have 3 choices:
|1. Cater to 50% medium grind||3 minutes||50% medium grind: properly extracted|
50% fine grind: overextracted (bitter, dry, hollow)
|2. Cater to 50% fine grind||1 minute||50% medium grind: underextracted (sour, salty, watery)|
50% fine grind: properly extracted
|3. Average the grinds, consider it medium-fine||2 minutes||50% medium grind: underextracted (sour, salty, watery)|
50% fine grind: overextracted (bitter, dry, hollow)
None of these options really works, not when compared to my perfectly extracted Batch 1.
And remember when choosing your grinder, flat burr grinders will do a better job than conical burr grinders in achieving a consistent grind.
How Much Ground Coffee Per Cup?
This is completely up to personal preference, but a good rule of thumb is 2 tablespoons (10 grams) for every 6 oz of coffee. For a bolder taste and stronger cup, use more ground coffee. For something milder or more subtle, use less.
The Specialty Coffee Association has more great information about coffee ratios.
Black Bear Coffee has a handy table with volumes of coffee and water for multiple serving sizes.
Just don’t grind more than you need. Why?
How Long Does Ground Coffee Last?
Coffee is best when it’s fresh, so I recommend grinding:
- Only the amount you need
- Only as you need it
Coffee will begin to degrade as soon as it’s ground, and many connoisseurs believe it will have a noticeable decrease in flavor after about 10-14 days. Nothing bad will happen if you store your ground coffee longer than that, but it won’t taste as fresh.
Can You Store Coffee in the Freezer?
Honestly, the jury is out on this one. I’d advise you avoid storing your coffee in the freezer for 2 reasons:
- Freezing and thawing, especially repeatedly, can damage the cellular structure of the coffee bean and redistribute water and oils within the bean
- Freezer burn and the associated odors can leach into your coffee
Coffee Bean Grind vs Espresso Bean Grind: What’s the Difference?
There isn’t one!
While espresso is best made with a fine grind, you can make a regular cup of Joe with that same grind, too.
Espresso isn’t defined by the type of coffee bean or grind. Instead, espresso is espresso because of the extraction process.
Related: 5 Best Krups Espresso Machines
More specifically, true espresso is defined by the following criteria:
- 200ºF water temperature
- 9 bars of pressure during extraction
- 25-30 seconds of extraction time
Nailing all of those criteria gives you an authentic espresso. Coming close gives you something close to espresso (but not quite a true espresso).