Recently I started a batch of sauerkraut, the first after several years. Unlike my previous batches this one is much smaller (half a head of cabbage, as opposed to several full heads), uses Morton's Kosher salt as opposed to sea salt, and fermentation was started in a large bowl as opposed to a crock.
Today I received a new crock, and transferred the batch from the bowl into the crock. The sauerkraut is about 72 hours old, and seems to be progresssing and expected–however as I transferred the kraut I noticed that the brine appeared slimy as it dripped. Aside from it's appearance when dripping it seems normal (I tasted a small amount, it smells like it should, and when the brine is standing still it appears normal. I also ran some of the extra brine through my fingers and it didn't feel slimy).
I'm curious if this is normal–perhaps either because the the kraut is relatively young (at only 3 days), or perhaps because of using "plain" kosher salt which may have additives such as anti-caking agents. Or perhaps it is perfectly normal and I've just never noticed it before, as I've never transferred a batch between vessels before.
Best Answer
In general, slimy brine is indicative of a fermentation problem. Your brine might be too weak (what concentration did you use?), it may be too warm, your brine might not cover the vegetables, there might be some air bubbles trapped in your ferment.
This article suggests that in the early days of sauerkraut fermentation, the concentration of slime forming bacteria - Leuconostoc - is relatively high and towards the end of fermentation it's too small to measure. It doesn't say anything about slimy brine, but it's possible that the brine is temporarily slimy in the early days of fermentation and as the acidity increases it dissipates. I've never checked a ferment this early, so I can't comment on it.
Personally, I would let it continue to ferment for a week or two and then see whether the perceived sliminess has dissipated or increased. It's possible that it's too early to tell. Slimy vegetables, without a doubt, should be discarded.
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