Bubbling Over: How to Prevent Mold in Sauerkraut

/ / Businesss, Consumer, People, Science

Three fermentation experts weigh in on one of the most common problems in fermenting vegetables: mold prevention. The fermenters include fermentation chef David Zilber (head of fermentation at Noma) and fermented sauerkraut producers Meg Chamberlain (co-owner of Fermenti Farm) and Courtlandt Jennings, (founder and CEO of Pickled Planet and TFA advisory board member).

How do you handle prevent mold in sauerkraut?

David Zilber, Noma: That is something you are constantly trying to fight back, especially when you lacto-ferment in something like a crock. There are so many variables that go into making a successful ferment. How clean was your vessel before you put the food in there? How clean were your hands, your utensils? How much salt did you use? How old was the cabbage you were even trying to ferment in the first place? Every little detail is basically another variable in the equation that leads to a fermented product being amazing or terrible. It’s a little bit like chaos theory, it’s a little bit like a butterfly flapping its wings and Thailand and causing a tornado in Ohio. But with lots of practice, you’ll begin to understand that, if it was 30 degrees that day, maybe things were getting a little too active, maybe the fermentation was happening a little bit too quickly. Maybe I opened it a couple times more than I should of and it was open to the air instead of being covered. So there’s lots of variables.  But I would say that, if you’re having a lot of trouble with mold, just up the salt percentage by a couple percent. It will make for a saltier sauerkraut, but it will actually help to keep those microbes at bay. (Science Friday)

Forced mold in sauerkraut experiment from Fermenti Farm.

Meg Chamberlain, Fermenti Farm: You must allow the ferment to thrive by creating a favorable environment with “Good Kitchen Practices.” So, to prevent mold in your ferment start by using only purified water, like reverse osmosis, distilled or boiled and cooled and-no tap water(municipal). Only use vegetable-based soap that is NOT anti-bacterial, like a good castile soap. Finally, only use dry fine Sea Salt, no mineral/no gourmet or iodized. Keep Fermenting and do not get discouraged! #youcanfermentthat #diyfermentation #idfermentthat

Courtlandt Jennings, Pickled Planet: Preventing mold when making sauerkraut is all about a controlled atmosphere. How well you maintain your situational cleanliness and fermenting atmosphere is my best clue for you. There are many ways to control atmosphere and every situation will be different based on many factors but be dillegent and your ferments will improve with practice.

This may not seem like an answer but it’s directional… as is most advice unless dealing with a consultant. Good luck and may the ferment force be with you!