This morning my ongoing poolish lived up to its troublemaking name. Over half of it (by weight) ran out over the counter overnight, through the screwed-down lid. This is after I saw it hitting the top last night and stirred it down before bed. In the photo below, the "after" photo is stirred down, but still pretty bubbly, so that's not even a completely fallen volume. I never fill the jar more than 1/3 full (at flat volume).
So, overnight, it at least sextupled in size.
Details: Commercial yeast 100% hydration bread flour poolish, maintained for about a month. Kitchen was probably 68F last night. I've let it rise and fall on the counter before, but the last two rest periods have been mostly in the fridge, if that matters.
So, primary question, what size jar, proportional to flat volume, should I use to be safe from overruns like this? I'd been going with 1/3 max, but then... this.
Secondary "why" questions to understand the answer:
- Is this level of expansion normal, or at least somewhat frequent, or was this a bizarre fluke?
- Did a counter rest after a couple fridge rests contribute to this explosion?
- If the "Blob that ate Cincinnati" effect is expected now and then, would a biga be more predictable due to its stiffer consistency?