The potato ferment: Progress report after 5 days

I started this ferment of raw potatoes on December 7. If you click the link, you will see how much the vegetables have collapsed. I observed the same thing when I fermented giardiniera (and an earlier batch collapsed even more, but I failed to get a photo).

I also saw the same sort of collapse when I fermented mushrooms.

The first time I fermented (raw) potatoes, I do not recall much collapse, but I followed (mostly) the instructions, which said to end fermentation after two days. (I actually went for 52 hours, but that’s close.) That fermentation did not use a starter. This time, I used some of the active fermentation liquid from my beet ferment that I had started the previous day, which was quite active. That took hold after 24 hours, producing a good string of bubbles when the jar was tilted.

The bubbles are not so active as that now, but they still appear, so fermentation continues. My plan this time is to continue the fermentation for two weeks (until January 21). In the meantime, I was just curious to see the potato pile collapse so much.