Wirsh Coffee Journal · Practical Brewing Guide
Espresso is often explained in “three stages,” but the chemistry does not switch cleanly between three boxes. The stages are a useful way to observe the shot—not a stopwatch formula for every roast.
Stage 1: Initial wetting and early flow
When water first contacts the puck, grounds hydrate, gases move and solubles begin dissolving. A machine with pre-infusion may deliberately slow this start. A machine without it can still brew excellent espresso when the puck is prepared well.
Stage 2: Building the main beverage
As water passes through the coffee bed, the cup accumulates acids, sugars, bitters and many other dissolved compounds. Different compounds extract at different rates, but everything overlaps. Pressure, temperature, distribution and particle size all shape what reaches your cup.
Stage 3: The later part of the shot
Late flow often changes color and concentration as the puck becomes more depleted. A pale stream can suggest a changing extraction, but it is not a universal signal to stop. Stop based on your target yield and flavor, then decide whether the next shot needs a different grind or ratio.
A better practical framework: dose, yield, time, taste
| What to track | Example starting point | Why it helps |
|---|---|---|
| Dose | 18 g | Keeps coffee input repeatable |
| Beverage yield | 36 g for a 1:2 ratio | Lets you compare concentration |
| Time | Record your own baseline | A diagnostic, not an absolute grade |
| Taste | Acidity, sweetness, bitterness, body | The actual target |
If your shot is disappointing
If it tastes sour and thin, a finer grind or different yield may help; if harsh and dry, experiment in the opposite direction while watching flow and channeling. The 1:2 espresso ratio guide explains why recipes are starting points, not rules.
