How to Log Preinfusion Without Guessing

First, establish what your machine offers

Before writing anything in a log, find out which situation you are in:

1. No preinfusion control. The machine has no user-facing preinfusion setting. Water arrives when the pump runs. You can still observe the first seconds, but you are not adjusting a phase.
2. Fixed preinfusion. The machine performs a preset wetting phase. You may be able to observe it but not change it.
3. Adjustable preinfusion. The machine exposes timing, pressure, or flow settings. You can change a parameter and record it.
4. Manual control. A lever, paddle, or flow-control valve lets you modulate the start by hand. This is a skill, and the "setting" is your action, not a number.

Check your machine's documentation. If you cannot confirm a feature, do not log it as though it exists. "Preinfusion: unknown" is an honest entry; inventing "3 seconds at 3 bar" is not.

What you can observe without controls

Even with no adjustable feature, the first seconds of a shot contain information:

• Time to first drop. How long from pump start until coffee appears.
• Appearance of the first drops. Dark and syrupy, pale and watery, or uneven across the basket.
• Whether flow starts evenly or from one spot.
• Whether the stream hesitates before running.
• Sound. Some machines change pitch as pressure builds.

These are observations, not settings. Log them under a field like "start behaviour" rather than "preinfusion pressure."

Fields for a preinfusion log

Use only the fields your setup supports.

If your machine has a pressure gauge, you can record what it reads during the start. If it does not, do not estimate pressure from sound. Note "no gauge" instead.

Logging manual preinfusion

Manual preinfusion is a technique, and technique is hard to log numerically. Record:

• What you did with the control: "held at low flow until first drops, then opened."
• How long you held it, if you timed it.
• What you saw at the puck.
• Whether the result was repeatable.

You can build a personal shorthand, such as "short hold" or "long hold," but define it once in the log so the entries stay comparable.

Why preinfusion notes are easy to fake

It is tempting to write "preinfused 4 seconds" because it sounds precise and knowledgeable. But if your machine does not have that control, the note is fiction. Worse, it corrupts your log: future comparisons will assume a variable that was never set.

The same applies to pressure. Without a gauge or a documented profile, a number is a guess. Use words for what you observed and leave the numbers to the fields you can measure.

A worked entry

For a machine with no adjustable preinfusion:

For a machine with adjustable preinfusion:

The second entry is more detailed because the setup supports it, not because it is better.

Using preinfusion notes in diagnosis

Preinfusion observations can help distinguish problems:

• Long time to first drop with an even puck: possibly a fine grind or a low start flow.
• First drop from one spot: distribution or channeling.
• Hesitant start then gush: a weak point opening.
• Very short time to first drop: coarse grind, low dose, or high start flow.

These are hypotheses. They become useful when combined with the rest of the log, not on their own.

Bottom line

Log what your machine can actually do. Identify whether preinfusion is absent, fixed, adjustable, or manual, then record only the fields that apply. Observe time to first drop and start behaviour even without controls. Never write a setting you did not set.