This month I am taking part in the Preserve the Bounty challenge over at Nourished Kitchen. Every week in August, we will be exploring a different traditional preservation method that doesn’t require canning. I found this idea especially intriguing since I have not had the best luck with canning—my lack of even basic canning equipment probably doesn’t help matters—and my limited freezer space is shrinking all the time. Since I don’t have a garden this year and can’t afford to make bulk purchases at the farmer’s market, I won’t be preserving food on such a large scale as many of the participants, but rather familiarizing myself with the techniques for future reference.

This week’s preservation method of choice was fermentation, a somewhat intimidating way for me to start the challenge since I have never tried it before. In essence, you create conditions that allow probiotic bacteria to begin breaking down the sugars in your food, producing lactic acid which preserves the food. It is almost like food alchemy, at once preserving your fresh produce and making it more bioavailable. As long as you ensure that your vegetables are completely submerged in the brine, it is actually safer than canning! Yogurt, kefir, kombucha and traditional ginger ale; sauerkraut, kimchi, and traditional pickles; cheeses, sourdough bread, and Moroccan preserved lemons are all examples of lacto-fermentation. I decided to go with my German roots for this week’s challenge and make a jar of sauerkraut, which I have honestly never liked despite my adoration of cabbage.

I started with a smallish head of cabbage from the farmer’s market, shredded as finely as possible. My food processor was out of commission, so I just used my chef’s knife and invested a bit of extra time, setting aside a few of the outer leaves first. Shredded, my little head of cabbage filled a large bowl, and I was concerned about getting it to fit into the jar I used, which I believe is a 2-quart; I had considered adding some shredded carrot or onion to the cabbage for bulk, but decided in the end to make a pure form of sauerkraut, at least for this first batch. In a similar spirit, I applied salt to my shreds and pounded them with my potato masher for 15 or 20 minutes, until they began to look wilted, lose bulk, and give off liquid—I figured it was done when the newly formed brine started splashing back up at me.

Although it isn’t strictly necessary for fermenting, I have plenty of whey in the fridge from making yogurt and ricotta cheese, so I included half a cup to give my sauerkraut a head-start. Then I packed it all firmly into my jar with a wooden spoon, trying to eliminate air bubbles. As the brine solution barely covered the cabbage, I dissolved a tablespoon of salt in a cup of water and topped it off that with. As you can see, I didn’t need to worry about that amount of cabbage in my jar, since the pounding really helped shrink it down; I could have easily made twice that amount.

Since I’m new at this, I obviously haven’t yet invested in a fermentation crock yet, and sauerkraut generally needs to be weighted down with something to ensure it stays well under the brine. Considering my options, I went with a method that uses a large Ziploc bag filled with water. I topped my pre-sauerkraut with a few of the reserved whole cabbage leaves, then placed the bottom of the bag into the jar, spreading it out and pressing it down with my hand; the top of the bag was folded back over the lip of the jar to make it easier to fill. Then I just poured in enough water to fill the remaining space in the jar, watching the brine level rise to make sure it wasn’t overflowing. I sealed up the bag and tucked it inside, and then locked down the lid of the jar.

My sauerkraut has been fermenting for 6 days now, and there is definitely some change happening—the cabbage has lost its bright green overtones, gas bubbles have been forming, and I’m starting to get some brine overflow. Good thing I have been storing the jar inside a larger plastic container, just in case. I’m kind of at a loss what to do with it now, though. Should I remove the plastic bag and store it in the fridge? Or leave the bag in place and store the jar in the basement? I suspect that it would be better to remove the bag, but I would welcome advice from more advanced fermenters. The brine that has been dripping out of the jar smells potently sour, in what I suspect is a good way from a health perspective, but this whole experience is somewhat alarming for a picky eater like me. My tolerance for sour foods like capers and vinegary sauces has increased somewhat over the past 5 years, but I still don’t really like pickles and I know I am going to have to ease my way into this sauerkraut very slowly.

Update 8/13/10: With the onset of this heat wave, I knew I should either move my sauerkraut to the basement or the fridge. It’s had about two weeks to ferment, and it would have languished in the basement, so I opted to transfer it to a quart container and pop it in the fridge. I was very pleased to see that there was no mold or scum inside my fermenting jar, and that the kraut had that tender-crisp texture that it should. I ate a forkful to get a flavor baseline, and it was quite sour and still on the salty side, so I think we would prefer to give it a bit more time to mellow out. I packed it in a glass quart jar recycled from spaghetti sauce, and it fit perfectly. Now I’m just crossing my fingers that it won’t overflow in the fridge like it did in the fermenting jar—but the cold should help retard the bacterial activity, right?