You cannot grind coffee beans into instant coffee, no matter how far down you turn the dial. Real instant coffee is brewed liquid that gets concentrated and dried, a definition that comes from The Craft and Science of Coffee, an Elsevier reference book edited by Britta Folmer.
So the right grind for your medium roast depends on what you actually mean by instant. For a fast, strong cup from fresh beans, grind fine, about the texture of table salt.
For true homemade instant, you need particles under 100 microns, or a brew-and-dehydrate route that starts coarse. Medium roast barely moves either target, because your brewing method, not the roast color, sets the grind.
What Instant Coffee Actually Is
Soluble instant coffee never came out of a bean grinder. The Craft and Science of Coffee defines it as roasted coffee extracted into liquid, then concentrated and dried into granules.
The Specialty Coffee Association explains why grinding cannot fake this. Roasted beans are about 70 percent insoluble plant fiber and only about 30 percent water-soluble compounds.
Grinding only increases surface area for extraction, as the SCA describes it. The insoluble part never dissolves and just stays suspended in the cup unless it is filtered out.
Commercial products handle this with a hybrid. According to the same Elsevier text, modern soluble coffees blend in roast particles milled below 100 microns to lift aroma, a format called microground.
Starbucks VIA instant sticks are one familiar example of the microground style. The home routes below borrow one idea or the other from those two factory processes.
If You Just Want a Quick, Strong Cup
Most people asking this question really just want speed. Grind fine, around the texture of table salt, then match the setting to your brewer.
Conventional grind targets are the honest starting point for any roast. Use the table below to match your grind setting to your brewing method.
| Brewing goal | Grind start, adjust by taste | Texture reference |
| Small, fast, strong brew | Fine | Table salt |
| Espresso shot or espresso-style concentrate | Very fine | Finer than table salt |
| AeroPress | Fine to medium-fine | Fine sand |
| Pour over | Medium-fine | Just coarser than table salt |
| Drip machine | Medium | Kosher salt |
| Cold brew | Coarse | Coarse sea salt |
| Microground instant powder, route one below | Under 100 microns | Flour |
None of these rows is a law, including for medium roast. A burr grinder makes them repeatable, because it crushes beans to a set gap, while a blade grinder chops randomly.
An espresso-capable conical model like the Baratza Encore ESP covers every espresso and filter row in that chart.
- Burrs: conical steel
- Adjustment: stepped settings from fine to coarse
- Espresso range: yes, fine enough for proper espresso and AeroPress use
That last row sits beyond everyday espresso grinders, and reaching it is its own project.
Route One: Microground Powder, Stirred Straight Into Water
Microground coffee, as The Craft and Science of Coffee describes the format, is roast coffee milled below 100 microns. At home the powder works alone, with no soluble granules to blend it into.
Barista Hustle’s grind size analysis puts the target in Turkish territory, with a particle distribution centered under 100 microns. Turkish grind is the traditional unfiltered brewing style, the finest setting in coffee.
The traditional hand tool for reaching it is a Turkish mill like the Sozen brass coffee grinder.
- Build: solid brass body
- Power: manual hand crank, no electricity
- Burr type: conical steel
- Target range: Turkish fine powder
A faster shortcut is a blade grinder run in short bursts, then sifted. Push the batch through a fine mesh stainless sieve, regrind whatever stays behind, and repeat until it feels like powdered sugar.
Medium roast fights this step, and Barista Hustle’s testing explains why. Compared with brittle dark beans, medium roasts hold more moisture and stay more elastic, so they shed fewer natural fines and need a tighter grinder setup.
To use the powder, stir one to one and a half teaspoons into a six ounce cup of hot, not boiling water. A thin silt layer at the bottom is normal, because that sediment is the insoluble fiber that can never dissolve.
Route Two: Grind Coarse, Brew Strong, Dry Into Crystals
This route copies the factory order of operations, extract, concentrate, then dry. The Craft and Science of Coffee describes soluble coffee production as exactly that sequence.
The grind at the concentrate step is coarse, in the same territory the coarse grind cold brew steeping relies on. A long, cool extraction with coarse particles is the usual way to keep the concentrate smooth instead of harsh.
A common home recipe steeps roughly one part coffee in four to six parts water for a strong extract. Filter it thoroughly before drying, since insoluble fines left behind would just sit in your crystals later.
Spread the filtered liquid thin on a silicone baking mat, then dry at the lowest heat an oven or food dehydrator can hold. A home freeze dryer is the premium option, chosen mainly because it preserves more of a medium roast’s delicate aromatics.
Once the sheet snaps dry, break it up and pulse it briefly in a clean spice grinder or mortar. These crystals dissolve completely, because the insoluble solids were filtered out before drying.
So Does Medium Roast Change the Grind Itself?
Not the grind targets, because brewing method sets grind size, not roast color. A medium roast uses the same targets as a light or dark roast for the same brewer.
What roast level does change is how beans behave under the burrs, per Barista Hustle’s data. That elasticity difference matters at the Turkish fine extreme, and it matters far less for everyday drip or pour over brewing.
Water heat is the one variable that does shift a little by roast. Common practice runs medium roasts slightly hotter than dark roasts, since darker beans give up their solubles more easily.
Bean age matters too, so check the best freshness window for your beans before buying a large bag. Fresh, well rested medium roast beans grind and brew more predictably than stale ones.
Tuning by Taste: The Two Adjustments
Bitter, drying, or hollow coffee can indicate a grind set too fine for your method. Step coarser, one small adjustment at a time.
Sour, thin, or weak coffee can indicate the opposite, a coarse grind that under extracted. Move finer in small steps.
Blame the setting before you blame the roast. If a drip machine is your brewer, our write up on the right grind for a drip machine goes deeper on that setup.
Whichever route you chose, one small test brew before a full batch will save you a lot of beans.
The Bottom Line
If instant means a fast cup, grind fine to match your brewer, near the texture of table salt. If it means true instant, mill under 100 microns for microground, or start coarse and dehydrate a strong concentrate.
Medium roast changes the drive rather than the destination, so run one test cup and adjust by taste.