Lessons in Wild Fermentation
We welcome guest contributor Miruna Stanica today to talk about the wild world of fermentation. Miruna lives here in Del Ray and we know her as a member of the Del Ray Yarn Bombers and a regular reader of the blog.
I was thrilled to learn from fermentation guru, Sandor Katz, a charismatic personality and author of the comprehensive reference book The Art of Fermentation. Katz’s lecture at the Heritage Harvest Festival at Monticello last month demystified what exactly happens when we preserve foods via fermentation, and his easygoing approach to the process gave me confidence to experiment when I came home.
Katz told us about so many foods we eat that are the products of fermentation – vegetables, dairy, bread, alcohol, vinegar, meat, and fish (lutefisk, gefilte fish, fish sauce), soy, coffee/cacao beans (which are soaked in water for a brief fermentation after they are harvested), and kombucha. Besides the practical reasons of preservation and nutriment enhancement, fermentation creates strong (and delicious!) flavors and smells: Think of the stinky cheeses, yeasty beers, and garlicky dill pickles we like to eat. Condiments like soy and fish sauce, shrimp paste, ketchup (which depends on vinegar) all get their flavor in part from fermentation.
Someone raised a hand and asked, “Is fermentation just spoiled food?” Katz said that, in fact, there is no clear demarcation between spoiling and fermenting food, but this does not mean you should start eating food that we traditionally think of as rotten! He explained that all living things are populated by colonies of microorganisms. This is what causes spoiling of living foods. Under different conditions, different microorganisms will develop. Fermentation means producing desirable microbial transformations by manipulating environmental conditions.
Katz taught us about two types of fermentation: wild fermentation, and fermentation with a starter like yeast or sourdough starter, or a SCOBY used to make kombucha and kefir. In wild fermentation: no starter culture is required. He demonstrated the wild ferment method in the workshop to make sauerkraut.
Steps for Making Sauerkraut
1. Chop the cabbage and put the pieces in a big mixing bowl. For this basic recipe, 1 pound of cabbage will yield 1 pint of sauerkraut. (Note: you can also include other vegetables such as carrots and peppers.)
2. Add salt to taste. Traditional fermentation recipes specify to add salt to 2% of the weight of the vegetables, but Katz says for cabbage, salting to taste is sufficient. Salting to a specific percentage is more important, he says, when you are pickling whole vegetables, such as cucumbers.
3. Start squeezing the ingredients with your hands, to mash, bruise and release juices. Keep squeezing until juice is oozing out of them (about 10 minutes).
4. Pack the cabbage into the jars, leaving about 1 inch of headroom at the top. Add filtered water if needed, just to cover the vegetables (but not chlorinated tap water, which discourages fermentation bacteria from growing). You might have enough liquid just from the squeezing. The main thing to remember is that for fermentation to occur, the vegetables must be submerged in liquid. Otherwise, bad oxygen-loving bacteria will grow (you will get spoilage rather than fermentation). If you protect it from oxygen, mold will not grow – and acidification also prevents things like E.coli, salmonella, and botulism.
5. Put the cap on, or cover with a cloth with a rubber band around it. If you are using a crock, you can put a plate on top of the liquid and weigh it down with a weight such as a clean stone or a Ziploc bag filled with water (I found a stone mortar bowl handy for this purpose.) As the cabbage ferments, the jars may leak a bit; removing lids to “burp” them avoids that. Mold may grow on top and this is fine; just remove it. Everything that is submerged in the liquid will taste fine.
6. Leave the jars sitting on a countertop. Remove lids and taste every day. The kraut is done when it tastes sour enough to you. For me, it took 6-7 days at room temperature. Sauerkraut can be kept indefinitely at cellar temperatures (about 55-60 degrees F), but can also be kept in the fridge when it has fermented enough.
My friend and I were so inspired that, the very next day, we put up three cabbage mixes.
- Chopped white cabbage, chopped bell pepper, grated carrot and salt.
- Chopped red and white cabbage with grated carrot, and minced garlic and horseradish root, salt.
- Chopped red and white cabbage with chopped scallions, and minced garlic and ginger, and sesame seeds, salt.
…and a week later had tasty fermented sauerkraut! I look forward to trying more fermentation projects with Katz’s book, The Art of Fermentation, close at hand.