I’ve been experimenting with my French Press lately but have been having trouble with leftover sediment at the bottom. So I did some research to see how to prevent this.
So, why is my French Press coffee grainy? Grainy French Press coffee is most often caused by a poor filter that doesn’t keep grounds out of your finished beverage. However, it can also be caused by plunging your French Press too quickly or grinding your beans too fine.
In the rest of this article I’ll share some techniques I’ve learned to make my French Press less grainy.
A coarser grind will prevent grounds from passing through the French Press plunger
Coarser, or more loosely ground, coffee beans are larger in size and are less likely to pass through the French Press filter. This will help to reduce excess graininess in the finished beverage.
If you’re using a blade grinder, simply grind your beans for a shorter amount of time and by using short bursts. This will produce a more coarse and even grind.
If you’re using a burr grinder, which is recommended, adjust your grind setting to a higher number.
Counterbalance a coarser grind with a longer brew time
Although coarser beans will reduce some sediment from your French Press, it will have a lower extraction rate due to them having a smaller surface area. This will result in a more sour and sometimes watery tasting cup of coffee.
If your coarser grind is producing an undesirable taste, you can counterbalance this under-extraction by brewing your grounds for a little longer. Most people recommend a 4 minute brew for French Press.
Don’t grind your beans too coarsely
Be careful not to grind your beans too coarsely or you will have a difficult time brewing a flavorful cup of coffee. If you’re still experiencing a grainy French Press coffee, try one of the other tips below.
Plunging more slowly will prevent grounds from being forced through your filter
Submerging your plunger too quickly can cause fine grainy sediment to pass through your filter due to the rapid pressure change. A slow plunge will cause some of the fine sediment to remain trapped under the rest of the grounds as they are being pressed down.
Pour slowly to prevent turbulence in your French Press
Pouring your French Press slowly will minimize the amount of grainy grounds that enter your mug.
Most of the undesirable grainy bits will settle to the bottom of your press while it brews. Lifting and pouring it carelessly will create turbulence and knock this sediment loose.
Pour through a secondary filter to catch any remaining grounds
Even though you have filtered your grounds once with the plunger, you can filter them a second time by pouring them through another filter. This will help you get rid of some of the excess grounds that made it through the first press.
Don’t use a paper filter
A paper filter is a great way to get rid of grainy French Press sediment. However, it also absorbs oils that add nice flavors and body to the coffee. I recommend using a metal filter, or even a fine cooking strainer.
Buy a French Press with a double filter
Some French Presses, like the Espro Press, have a second filter already built into the design. This prevents the need for a make-shift filter of your own or add another step to your brewing process.
Replace your French Press plunger
It’s possible that the rubber seal on your plunger is starting to warp or crack. This could cause grinds to escape through the edges between the plunger and glass container.
You might be able to find replacement seals. Or you might consider buying a new French Press altogether.
Use a burr grinder to produce a more even ground
Burr grinders are often recommended for French Press enthusiasts because they produce a more even grind compared to blade grinders.
A low-quality blade grinder will unevenly grind your beans and is likely to produce many grainy coffee bits that will end up as sediment in the bottom of your mug. If you’re serious about taking your coffee to the next level, I highly recommend investing in a burr grinder.
There are two main types of conical burr grinders: ceramic and stainless steel.
Ceramic burr grinders are usually less expensive and a bit less durable, but are still a huge improvement over a blade grinder. Stainless steel burrs are more reliable, will often produce a more uniform grind but are more expensive.
There are many great manual burr grinders in the $50 – $100 range.
Replace your coffee grinder burrs to produce more evenly ground beans
Dull or chipped coffee grinder burrs will cause your beans to grind unevenly. This increases the likelihood that your grounds will include grainy fragments that will pass through your French Press filter and end up in your mug.
Inspect the quality of your coffee burrs to see if they need replacing.
Grind your beans in bursts if you’re using a blade grinder
If you are using a blade grinder, you can achieve a more even grind by grinding your beans in short bursts instead of one long go. Blade grinders are better for finely ground blends, which is a little different from the coarse grind common for French Press coffee.