Tending the ferment
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What you are actually doing
Three things, repeatedly, for three to six weeks depending on temperature.
- Remove the scum from the surface as it appears.
- Confirm the vegetables are still under the brine, and that the weight has not shifted as gas production lifted them.
- Write down what you saw and when, because this is the only diagnostic the batch will ever have.
Scum is not the same as the ferment
The cloudiness that develops through a healthy fermentation and the film that forms on the surface are different things, and confusing them sends people in two wrong directions: discarding good batches, or leaving a surface film in place because cloudiness was described as normal. The cloudy brine page is the one that separates those, and it is worth reading before the first batch rather than during it.
Why the log matters more here than anywhere else
A quick pickle can be checked in the finished jar: measure the equilibrium pH and you know. A ferment cannot be re-run, and by the time a fault shows up the conditions that caused it are weeks gone. The log is what converts a soft batch from a mystery into a cause, and the fields that matter are the ones you will want to compare across batches.
- Date brined, and the brine weights.
- Daily or near-daily temperature, ideally a maximum rather than a spot reading.
- When scum was removed, and how much.
- When it was judged finished, and on what basis.
This is unglamorous and it is the difference between a craft that improves and one that repeats. The maker who can say "the soft batch was the one that sat at 82F for four afternoons in week two" fixes it. The maker without a log buys a new crock.
Build the schedule around the first week
Attention is not needed evenly. Gas production and surface activity are heaviest early, which is when the weight shifts and when a film first establishes, so the first week wants looking at daily and the last two tolerate every few days. Spreading the same total effort evenly across the run is how people miss the week that matters while feeling diligent.
That uneven shape is also what makes staggered starts worth planning. Ten vessels all brined on the same day put their heaviest demand in the same week, and that week is in the middle of the picking window when there is least slack. Starting them across several days costs nothing and moves the load off a single afternoon.