Want to know about kimchi, other Asian ferments, and fermentation in general? We’re here for you. Here are all the questions that are frequently asked from customers at farmers markets and sampling demos.
Q: What is kimchi?
A: Kimchi is a Korean fermented vegetable product, similar to sauerkraut. Like sauerkraut, it’s packed in a salt brine and left unrefrigerated. During that time, good microbes called lactobacillus, also known as probiotics, preserve the vegetables inside the brine by making carbon dioxide and lactic acid. This is why kimchi and other fermented vegetables taste sour. The unique thing about kimchi is the addition of chili pepper flakes, called gochugaru in Korean. The most well known type of kimchi is made with cabbage, but there are all kinds of kimchi made with an infinite variety of vegetables.
Q: Do you add vinegar to kimchi?
A: Nope! All the acid is naturally produced by lactobacillus, some of the same bacteria found in the human gut biome that help us digest food.
Q: How long does kimchi last?
A: There are a lot of variables to this question! It can last from several weeks to several years. The bacteria found in naturally fermented kimchi keep it preserved so you can leave it unrefrigerated. Warmer weather speeds up bacteria activity, and cooler weather slows it down. Well preserved kimchi doesn’t necessarily go “bad,” but it does get soft as it ages.
Q: Do I have to refrigerate my kimchi?
A: Generally, it’s recommend. Although kimchi is technically safe at room temperature, warm weather makes it softer faster. Refrigerated kimchi can sometimes last up to a year or more before going soft.
Q: Does the “best by” date on the kimchi jar have anything to do with when the jar is opened?
A: Nope! Kimchi is a living food, and whether you open the jar or not, the bacteria are in there working away. We do recommend refrigerating the kimchi to slow down fermentation so it will stay crunchy longer. Our kimchi is not sealed or pasteurized in any way (this would kill the probiotics).
Q: My kimchi jar lid is bulging a little and there’s a bit of liquid leaking out! Has my kimchi gone bad??
A: The probiotics in the kimchi create carbon dioxide, and especially in warm weather and if the jar has not been refrigerated, there may be extra fermentation activity causing excess gas and bubbling. This is perfectly normal and safe. Your kimchi is still fine to eat. Wipe down the jar and refrigerate to slow this reaction. (We’ve been conditioned with jarred/canned and pasteurized foods to look out for bulging and leaking jars, but this is a completely different kind of reaction caused by botulism bacteria in heat-treated, acidified foods and is not what is happening with kimchi and other naturally fermented, living foods.)
Q: What can I do with soft kimchi? I found a jar of kimchi in the back of my fridge and it’s mushy.
A: Soft kimchi is WONDERFUL in spicy Asian soups, or kimchi fried rice!
Q: I tried to make kimchi at home and it didn’t turn out.
A: We get this question a lot at markets! Without knowing the specific circumstances of what you did and the environment where your kimchi fermented, we can’t exactly give you answers to what went wrong. But kimchi and other lactofermented vegetables prefer a salty environment and the exclusion of oxygen. Chances are is that you didn’t add enough salt, or that you exposed your ferment to too much oxygen.
Q: Do I have to add salt?
A: Yes. The lactobacillus bacteria use the salty environment to their advantage! Most bacteria and other “bad” microbes can’t survive in a salty environment, but lactobacillus can. Without enough salt, your ferment will begin to host other organisms, making it unsafe. Unfortunately, most lactoferments are not a low-sodium food.
Q: I want to learn more about fermentation. Do you have resources?
A: Our favorite fermentation resource is the The Noma Guide to Fermentation by David Zilber and Rene Redzeppi. This book is a great intro to fermentation from two chefs at the world-famous Noma restaurant in Denmark. We also recommend the fermentation sessions at Kojicon, an annual virtual fermentation conference. If you’d prefer a hands-on approach, check out our upcoming in-person kimchi classes!
Q: I want to learn more about kimchi and Korean food! Do you have resources?
A: Here are some fun resources to get you started!
- Youtube: Maangchi, Aaron and Claire
- Netflix: A Nation of Kimchi
- Book: Wookwan’s Korean Temple Food
