Getting Your Coffee Grind Right
How To Get Your Coffee Grind Right For Great Espresso
Why Coffee Grind Size Matters
Grinding coffee beans breaks them into smaller pieces, increasing their surface area and exposing them to water. This allows the water to extract the soluble compounds that give coffee its taste and aroma. However, not all compounds are extracted at the same rate. Some are extracted quickly, while others take longer. The rate of extraction depends on several factors, such as water temperature, pressure, contact time, and grind size.
Grind size affects how fast or slow the water flows through the coffee grounds and their contact time. A finer grind means more surface area, more resistance, and longer contact time. This results in a higher extraction rate, which can bring out more flavour, sweetness, acidity, and bitterness from your coffee beans. A coarser grind means less surface area, less resistance, and shorter contact time. This results in a lower extraction rate, which can bring out less flavour, sweetness, acidity, and bitterness.
The Perfect Shot Of Espresso
What are you even looking for in your coffee?
Timing
Your espresso should take 25-30 seconds to extract for a double shot.
Looks
You're wanting to see a nice, dark brown body, topped with a creamy, lighter brown, slightly foamy-looking crema.
Taste
You want to taste a balanced, flavourful espresso that isn't too bitter, sour, burnt or ashy tasting.
The Perfect Coffee Grind
So here's the tricky part: there is no "one-size-fits-all" grind size for coffee. It'll vary slightly, depending on the beans you're using, the grinder you're using, and even the humidity! So what you want to work out is your starting point, then learn how to adjust appropriately from there.
To begin with, you want your ground coffee to roughly resemble sand - not powdery or too fine, but not gravelly or coarse either. Once you've reached that sandy consistency, you can start extracting your espresso and adjust as needed.
What To Do Next
If your espresso extracts beautifully, then fantastic! Enjoy your delicious coffee. But if not, then something needs adjusting. Assuming you are using fresh, good quality coffee beans AND are using the correct amount/tamping at the right pressure, etc, here's what to do if...
Your espresso is coming out too quickly/gushing, tasting sour, acidic, or weak.
Your grind may be too coarse or you don't have enough ground coffee in your porter filter. Try adjusting the grinder slightly finer.
Your espresso is coming out too slowly, tastes burnt or bitter, or is clogging up your machine or grinder
Your grind may to be too fine or you have to much ground coffee in your porter filter. Try adjusting the grinder slightly coarser.
Important Things To Know
When making adjustments to your grind, always adjust a tiny amount at a time. You should also run your grinder for 2-3 seconds to remove any old coffee grinds from the previous setting, and ensure you aren't changing any other variable (dosage, tamping pressure, etc) at the same time - otherwise, you won't be able to tell what's working (or what isn't!).
Need some more guidance? Check out our other blog posts!
