Can sauerkraut develop a mother?

My last batch of sauerkraut was different from what I usually make. I used the same ingredients and followed the same steps, but after three days of fermenting on the countertop, the liquid was somehow more viscous that usual. Especially at the top, almost like a mother in the making. I've never had this happen before and I'm puzzled.

My recipe isn't a true sauerkraut because I add grated carrot and apple. I've been doing this for about a year now, and always had typical lacto-fermented results with liquidy "juice." Maybe the apple caused it? Odd, because it's never done it before.

The only difference in my preparation was that I added some of the liquid from my previous batch to the brine for the new (usually I add whey).

It smelled and tasted delicious, but I'm wondering about it and curious if anyone else has had this happen. Or has a possible explanation.

Sweet contents in a brine ferment sometimes cause gloopy dextran to form. I mostly see this with beets, but sometimes carrot. Often, but not always, if you just let it ferment longer, the next wave of bacteria to come online (or something...that's how I think about it but I don't really know what's going on) will metabolize it away. When it's all snotty like that it's pretty unappealing, but once it's gone it's back to normal. And the dextran isn't unhealthy, just gross.

Thanks Christopher, that makes sense. I did rinse it off before we ate it, lol. It's just odd to me that it's never happened before. Right now it's in the fridge because it's tart enough for our taste. But I'll have to experiment to experience what you describe.

There are 52 mentions of dextran at the Wild Fermentation support forum, which is where I first learned about the phenomenon. I'm not sure if any of it is particularly useful or interesting, but a shortcut to get there is:
https://wildfermentationforum.com/search.php?keywords=dextran

(Probably there is some interesting discussion but also a lot of "hey, my carrots are slimy" followed by someone explaining about dextran at the newbie level that would have to be waded through.)

The sugar in apples (and carrots) ferments to alcohol, which ferments via mother into vinegar.

In general, lacto-fermentation needs about a week to begin. Before that, various microbes are still fighting it out to see who will win. I know nothing about dextra-anything, but I learned a lot about the general topic in a microbiology class and I've been fermenting all sorts of vegetables for almost 10 years. I usually don't do sweet things except carrots along with other more typical veggies like green beans.

Sandor Katz at that site is far more of an expert than I am, so listen to him, but my input is what I learned in school and from experience: the "good bacteria" (lactobacillus types, in this case) don't form in any worthwhile numbers for our health until a few weeks, or even a month if you can wait that long and can enjoy the veggies at that stage of flavor. Longer is better, though beyond a couple months is debatable as to whether the probiotics are still growing, and things get pretty mushy over time. For sauerkraut and most veggies I wait at least a month.

The bacteria we want is found in dirt, which means it's on the outside of your veggies, so just lightly rinse them off. Don't peel anything if you can help it. You won't need to use any juice from previous batches or whey if your salt ratio is good. I only use juice from previous batches on something that won't have any dirt on it, like when I made mustard. I put the usual sauerkraut ratio of salt & water, but I also put some previous juice to get it started because I have no idea how the mustard seeds I bought in a bag were grown or washed or how long they were dried out for, so I had to assume there'd be no good bacteria on it and it'd have to come from somewhere.

I had dextran appeaer recently in a batch of sichuan pickles (chayote and carrots). I want to say it was colder than usual, or something, and someone here was talking about it. I kept the brine for a few more batches but it did keep getting slimy and then resolving-- but it never did form a super pickle mother, unfortunately!