Super Food Nerds: Make Your Own Sauerkraut
I, for one. Here, let me begin. Sauerkraut — nothing more than shredded cabbage, salt and time — is vegetable fermentation in its purest form. It is to cabbage as wine is to grapes: a complex, lively, astonishingly delicious ennoblement. (Kimchi, which involves more flavoring and manipulation, is a nearer analogue to beer.) The comparison to wine may seem a bridge too far for sauerkraut if all you know is the dull jarred stuff that upholsters billions of hot dogs. But as anyone who has ever made it at home understands, good sauerkraut, with its irresistible mix of salty and savory, crunchy and tangy, is a sophisticated thing of beauty.
And the good news is that the homemade stuff is something anyone can make. It's not just that the requirements are minimal — cabbage, salt, jar — it's that cabbage wants to become sauerkraut. Everything necessary for the magical transformation — the bacterial strains that do the fermenting, the sugars they metabolize in lactic acid, even the brine the cabbage will ferment under — they're all right there before you’ve even begun, native to every head of cabbage. The only thing missing is salt, and even that is not absolutely necessary.
This sense that at some level sauerkraut is already there, and that in making it you are merely stewarding a natural process of self-actualization, accounts for the soft spot many fermentation enthusiasts have for the stuff. My friend Jeffrey Yoskowitz, a fermentation expert and founder of The Gefilteria, an artisanal producer of traditional Jewish foods, counts sauerkraut, which he describes as "the simplest and most intimate" of fermentation projects, as his favorite ferment. I couldn’t agree more.
Sauerkraut is distinguished by not only its profound simplicity but also its duration: It is slow — weeks slower than kimchi, dill pickles or just about any other vegetable ferment you can name. (In this regard too, it begs comparison with wine.) Four to six weeks is the general rule for high-quality 'kraut. The reason for this lengthy gestation is that the journey from cabbage to 'kraut is a process of very slow acidification, involving the succession of three species of lactic-acid bacteria. Basically, it's a slow-moving bacterial relay race: The Leuconostocs get things started, producing lots of carbon dioxide and enough lactic acid to set the conditions for Lactobacillus plantarum to take over. When the ‘kraut reaches 1.5 percent lactic acid, Lactobacillus pentoaceticus goes to work, until eventually all the remaining cabbage sugars have been converted to lactic acid. At that point the sauerkraut is about 2.5 percent lactic acid and ready for the refrigerator. The final product is highly acidic (kimchi, by contrast, clocks in at 1 percent lactic acid) and highly complex, with interesting fruity and floral components contributed by low levels of alcohol and yeast.
But you hardly need a Ph.D. in sauerkraut biology to make sauerkraut. In truth, the process is almost too simple to merit a recipe: Shred cabbage, salt it, submerge it under a brine of its own making, and keep it there for a good long time. But attention to the finer points yields big rewards.
Super Food Nerds is a column written in alternating installments by Rupa (food and beverage editor, culinary staff) and Jonathan (research librarian, same place). Each post will be dedicated to a particular topic — how to DIY something you don’t normally DIY, how to perfect a dish usually taken for granted, plus the best techniques, underlying chemistries and a handful of inexplicable preferences. Basically, if they can overthink it, they’re on it.