Hi from NH where you did a great workshop in Walpole a few years back!
I've been brewing kombucha since Wild Fermentation first came out. All of a sudden now, my culture stays unbalanced. It stays too sweet even while it goes quite tart. Oddly, I've started with a new culture three times, and used a new brewing vessel twice. What could be going on? Any suggestions for correcting it?
I've also been making (fabulous, if I do say so) garlic dill pickles with the recipe in Wild Fermentation. This year, I processed 2 half gallon jars on the same day with cukes and dill picked at the same time from the same garden. I processed them in the same way. Nevertheless, one jar was mush when I opened it, while the other was quite lovely and crispy. What's that about?
BTW, a couple times over the years, I've found a kombucha- or vinegar-like mother at the top of a pickle jar, after it's had no contact (that I'm aware of) with either. What's up with that?
Just a comment on something I found interesting: I'm on town water. We have 2 sources. One time I was making pickles and couldn't get hardly any of the salt to dissolve. I asked our water guys about it. They said we were on the secondary source and that it has lots of magnesium in it, which would make dissolving salt difficult. All of those pickles were still crispy a year and a half later!
I'm not sure what to tell you about your kombucha. The fermentation metabolizes sugars into acids, so I don't see how it can get acid without losing sweetness. Wish I could tell you what the problem was....
On the mushy pickles: perhaps one batch of cukes had more residue of the flower blossoms, which are particularly rich in the enzymes that digest pectins and make pickles crunchy? Or one jar got more grape leaves?
I've heard of mothers forming on pickles, even without kombucha nearby. I think it's a vinegar mother.
Minerals in water can affect ferments in a number of different ways.