Once kimchi has gotten its hooks into you — stinky and fiery as it may be — life becomes unthinkable without the fermented Korean dish. It makes masochists of those who happily endure its scorch — even Super Food Nerds like myself. Kimchi packs the earthy-fruity wallop of a good hot sauce, the crunch and tang of a great pickle, and, rumbling beneath it all, a funky-savory-umami bass note uniquely its own. Any food that can do one of those things well deserves a place in your kitchen. A food that excels at all three is, quite simply, indispensable.
As I embarked on the quest to develop a worthy kimchi recipe, I enlisted the help of my colleague Esther Choi, a marvelous chef who, having grown up in a traditional Korean kitchen, has kimchi pretty much coursing through her veins.
What I learned from Esther could fill a book; I’ll stick to the highlights. According to Esther, kimchi is more method than dish. There are hundreds of harvest-preserving kimchis: summer kimchis, fall kimchis, kimchis meant for eating fresh and those meant to see you through a season. Once you get the hang of the method, nearly any vegetable can be kimcheed. I once tasted watermelon rind kimchi Esther made; it was spectacular.
The method itself is remarkably simple: a variation on the same lacto-fermentation process behind sauerkraut and sour pickles. It starts with the application of salt to vegetables, either by brining or dry salting. Once the salt has thoroughly penetrated, the vegetables are drained, flavored and sealed tightly into jars. Once jarred, native strains of lactic acid bacteria go to work digesting available sugars into lactic acid — acidifying and thereby preserving — the vegetables.
What sets kimchi apart, however, is the flavoring process. Once salted, kimchi vegetables are coated in a flavor-bomb of a sauce, typically comprised of an alarming quantity of garlic and onion; a fearsome volume of chile flakes; the ominous presence of some fresh or fermented sea creature (fish sauce and salted shrimp are the most common, but oysters, fish and squid make frequent appearances); and, binding it all together, a glutinous paste made from sweet rice flour. Oh, also some sugar and/or fruit, typically an Asian pear, is included to balance all that chile heat.
The mixture looks infernal — particularly when you’re kneading it into the cabbage with your (gloved) hands — but this particular alchemy of pungent, spicy, salty, sweet and savory is the delicious quintessence of Korean cooking.
Making kimchi is not difficult, but it can be tricky. Unlike sauerkraut, kimchi fermentation starts fast and, based on the experience of a couple of disappointingly gnarly test batches, seems more apt to spin out of control. (I’m guessing the added presence of fermentable sugars and starches in the “sauce” accounts for this.)
The good news is that, unlike sauerkraut, kimchi is happy to do all its fermenting in the temperature-controlled environs of the refrigerator. Though most recipes advise kick-starting fermentation at room temperature for anywhere from 1 day to 1 week before transferring kimchi to the refrigerator, trial and error (and Esther) have taught me to do otherwise. Low-temperature fermentation may slow things down considerably, but it produces more reliable, and equally delicious, results.
This was one of my biggest takeaways: Kimchi doesn’t need to be babied. You don’t have to stow it someplace safe and refrain at all costs from disturbing it for a set period of time. Quite the contrary! You should always be testing and tasting every step of the way, because at every stage — from the brining (salty enough?) to the saucing (spicy enough? sweet enough?) to the fermenting (sour yet?) — kimchi should taste good. That’s how you know you’re on the right track. And it’s liberating in a fermentation project like this to allow yourself permission to let your palate guide you.
As the kimchi ages, its changing flavor guides how you should eat it. Young kimchi is generally used as a side dish, salad or table condiment. (It also makes a great sandwich element.) Crunchy and refreshing, it offers a welcome counterpoint to an amazing variety of rich, fatty or starchy foods. As kimchi matures, growing more funky, sour and spicy, it lends itself better to cooking: great for soups and stews or, my favorite, kimchi fried rice.
Somewhere in middle age, after two or three weeks, kimchi sometimes accumulates enough CO2 to become slightly effervescent. This tongue-prickling fizz — palate-cleansing in its effect, much like Champagne — is, according to Esther, the mark of really good kimchi. If you manage to achieve it, congratulations. Pour a flute of kimchi juice and toast yourself!
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.