Can we talk about the 'burp your jar' advice for sauerkraut?

I was making kraut for about a year, always just unscrewing the lid a bit each day to let gas out. My last batch, the one I started in early March, got a weird, almost yeasty smell after a week. I opened it and saw a faint, white film starting on top of the brine. I freaked out and called my friend who runs a farm stand. She asked me one question: 'Are you opening it over the sink?' I was. She told me that lifting the lid lets in a ton of airborne stuff, and that's probably what seeded the film. The right way is to just press down on the lid to let bubbles rise without breaking the seal, or use a proper airlock. I tossed that batch, but it was a cheap lesson. Has anyone else had a batch go off from burping it wrong?

3 comments

3 Comments

ivan2113mo ago

Yeah, that film is kahm yeast, it's harmless but a sign of too much oxygen.

sage_lewis103mo ago

Totally feel you on that. My first few batches got kahm yeast from burping over the sink too. Pressing down on the lid without opening it is the real trick, lets the gas escape without letting new air in. A cheap airlock setup is even better if you make kraut a lot, stops the guesswork. That yeasty smell means it's working with oxygen, which you don't want. Your friend gave you solid advice, it's a common mistake.

barbara3991mo ago

How did your friend figure out you were opening it over the sink? My neighbor had the same issue and it was because she always opened her jars right after washing dishes. The steam and stuff in the air from the damp sink area just falls right in. I switched to a proper ferment lid with a silicone gasket and it stopped happening. Those one-piece plastic lids that click down work good too, they let gas out but not much air gets in. Its a cheap fix once you know what the problem really is.