Grinding alone cannot make true instant coffee, because roughly 70% of a roasted bean is insoluble cellulose that water will never dissolve. What grinding can do is set you up for one of two real paths: brew a strong fair-trade concentrate to dehydrate into genuine instant crystals, or grind to an ultra-fine powder that suspends in hot water like the microground “instant-style” products on store shelves.
Why Grinding Cannot Make Coffee Dissolve
Instant coffee is not just finely ground coffee. It is brewed liquid with the water removed, usually by freeze-drying or spray-drying, as described in Coffee: Recent Developments (Clarke and Vitzthum, Blackwell Science).
The book explains that commercial soluble coffee manufacture grinds roasted beans to a fairly coarse size, around 1.0 to 1.5 mm, then extracts them in industrial percolator columns to produce a liquor containing roughly 15 to 30% solubles before drying. That means even the biggest instant coffee factories grind coarser than many home brewers expect, because the grind only has to suit the extraction step, not the cup.
A fair-trade bean behaves no differently chemically than a conventional bean at this stage. The fair-trade certification affects sourcing and price paid to growers, not solubility, so your grind decisions follow the same science as any specialty Arabica.
Method One: Grinding for a Dehydrated Concentrate
If you plan to brew a high-strength concentrate and dry it into true instant coffee, match your grind to your extraction method rather than defaulting to “fine.” Cold extraction favors a very coarse grind because the long steep time does the work, while faster hot extraction calls for finer particles. A burr grinder keeps particle size consistent, and consistency matters more than any single setting here.
Grind only what you will extract within minutes. Long-exposed grounds lose the volatile aromatics that make a concentrate worth drying in the first place, so the freshness window of the beans themselves still shapes the final powder.
Use the table below to pick the right grind size before you brew your concentrate.
| Extraction Approach | Starting Grind | Typical Particle Feel | Why It Fits |
|---|---|---|---|
| Cold brew concentrate | Extra coarse | Kosher salt | Long steep pulls solubles slowly without bitterness |
| French press or immersion | Coarse | Sea salt | Filters cleanly through mesh before drying |
| Hot percolation or espresso-style | Fine | Table salt | Pressure and heat maximize soluble yield quickly |
Brew your concentrate strong but balanced. The SCA Coffee Standards define balanced brewed flavor as roughly 18 to 22% extraction, and exceeding that range is a common cause of harsh, drying flavors even in a concentrate destined for the dryer.
A quality conical burr grinder makes these coarse settings far more repeatable than a blade unit. The Baratza Encore burr grinder covers everything from cold-brew coarse to espresso-fine, which spans every concentrate method above.
Method Two: Microground “Instant-Style” Powder
The second path skips the dryer entirely. Grind your fair-trade beans to a Turkish-grade ultra-fine powder, below roughly 100 microns, and stir it straight into hot water.
Research collected in The Craft and Science of Coffee (Folmer, Elsevier) notes that particles below about 100 microns minimize perception of grittiness in the cup, even though the insoluble cellulose remains and settles as sediment. This is the same principle behind commercial microground blends like Starbucks VIA, which pair soluble granules with suspended ultra-fine particles.
- Target feel: like talcum powder or baking flour, with no grit when rubbed between fingers
- Dose: roughly 1 to 2 g of powder per 200 mL of near-boiling water
- Sediment: expect a fine silt at the bottom of the cup, since the solids never dissolve
Most home burr grinders cannot reach this fineness. The standard tools are Turkish hand mills with brass burrs or commercial flat-burr machines such as the Turkish hand grinder, which produce the powder consistency this method requires.
Fair-trade lots are frequently lighter-roasted specialty Arabica, and roast level shifts the target slightly. Denser light and medium roasts resist grinding and can benefit from a slightly finer setting, while brittle dark roasts shed fines easily and grind better with a slightly coarser setting to avoid excess dust.
If you already grind fine for other methods, our guides on grinding fair-trade coffee for espresso and grinding fair-trade coffee for Turkish coffee cover similar burr territory without the drying step.
Adjusting by Taste
Whichever path you choose, troubleshoot by flavor rather than by dial numbers. A weak, thin result can indicate your grind was too coarse for the contact time you gave it, so move finer in small steps and taste again.
Harsh, bitter flavors can indicate you went too fine or too hot for your method. Back off slightly coarser and retest before committing a whole batch of beans to the grinder.
Avoid overheating the beans during grinding. Pulsing a blade grinder for long stretches heats the grounds and flattens aroma, so short bursts with rest periods protect the flavor you paid a fair-trade premium for.
Wholeness of the bean matters before grinding too: our companion piece on how fresh fair-trade coffee should be for instant coffee covers the window between roast and process.
For an affordable way to check your settings, a simple 0.1 g digital scale keeps doses consistent once you find a grind that tastes right, since microground powder is light and fluffy by volume.
Conclusion
Grind fair-trade beans fine for fast hot extraction, coarse for long cold extraction, or under 100 microns for microground powder stirred straight into water. No grind setting makes coffee truly dissolve, so pick the concentrate-and-dry path if you want genuine instant coffee. Start with a burr grinder, one small test batch, and a taste before you commit the full bag.