Kimchi recipe: salting, seasoning and fermenting napa cabbage

This kimchi recipe is the everyday napa cabbage kind. The cabbage is salted for a couple of hours, rinsed, coated in a paste of chilli flakes, garlic, ginger and salted seafood, then left at room temperature for a day or two and moved to the fridge, where it keeps souring for weeks.

Cabbage is only the best known version. The same salt, season and wait method turns radish, cucumber and spring onion into kimchi too, and once a jar has gone properly sour it stops being a side dish and becomes the base of kimchi jjigae.

What is in kimchi

Every kind goes through four stages. The vegetable is salted so it gives up water and softens. It is rinsed. It is coated in a seasoning paste. Then it is left alone while lactic acid bacteria ferment it.

The paste carries the flavour: gochugaru (Korean chilli flakes), garlic, ginger, spring onion, and a salty, savoury base of jeotgal, salted fermented seafood such as tiny shrimp, or fish sauce, or both. Many recipes, including both of the ones cited on this page, also stir in a thin porridge of glutinous rice flour. UNESCO’s own definition is short: preserved vegetables “seasoned with spices and fermented seafood”. There is no vinegar in any of it. The sourness comes from fermentation.

The recipe: whole napa cabbage kimchi

The quantities below are from Maangchi’s traditional napa cabbage kimchi (tongbaechu-kimchi). They turn 2.7 kg (6 lb) of cabbage into about 3.6 kg (8 lb) of kimchi. The method below is a summary; her page has the full version and a video.

Kimchi ingredients

• Napa cabbage, 2.7 kg (6 lb)
• Kosher salt, ½ cup (72 g)
• For the porridge: 2 cups water, 2 tablespoons sweet rice flour, 2 tablespoons turbinado sugar
• Korean radish, 2 cups in matchsticks
• Carrot, 1 cup in matchsticks
• Green onions, 7 to 8, chopped
• Asian chives and minari (water dropwort), 1 cup each, both optional
• Garlic, ½ cup minced (about 24 cloves)
• Ginger, 2 teaspoons minced
• Onion, 1 medium, minced
• Fish sauce, ½ cup
• Salted fermented shrimp (saeujeot) with its brine, ¼ cup, chopped
• Gochugaru, 2 cups

Method

1. Trim the base of each cabbage. Cut a short slit into the stem end and pull the head apart into halves by hand. Cut a second slit through the core of each half, about 5 cm (2 in) above the stem, so the leaves loosen but stay attached.
2. Dip the halves in water. Lift each leaf and scatter salt between them, using more on the thick white stems than on the green tops.
3. Leave the cabbage for 2 hours, turning the halves over every 30 minutes so the salt works evenly.
4. Rinse the halves several times under cold running water. Pull each one into quarters along the slit, cut out the core, rinse once more and leave to drain in a colander.
5. For the porridge, heat the water and sweet rice flour over medium heat for about 10 minutes, until it bubbles. Add the sugar, stir for another minute and let it cool completely.
6. Mix the cold porridge with the garlic, ginger, onion, fish sauce, salted shrimp and gochugaru into a thin paste. Fold in the radish, carrot, green onion and any chives or minari.
7. Spread paste over every leaf of each quarter, fold the quarter over on itself into a bundle and pack the bundles tightly into a jar, tub or onggi. Press down to push out air.
8. Leave it at room temperature for a day or two. It has started fermenting when it smells and tastes sour and pressing on the top brings bubbles up from underneath. Then move it to the fridge, which slows the fermentation down.

Korean Bapsang’s traditional kimchi salts differently, and the difference is worth knowing if your cabbage is large. Half a cup of coarse sea salt is dissolved in 5 cups of water as a bath for the quarters, another half cup is sprinkled onto the stems, and the cabbage sits for 6 to 8 hours, with the bottom pieces moved to the top every 2 to 3 hours. That recipe gives the finished kimchi about two weeks in the fridge before its flavour has fully developed.

Salt and temperature: the numbers behind a safe batch

The clearest published figures come from the BC Centre for Disease Control, whose kimchi guideline is written for food businesses in British Columbia. It recommends salting in a brine of 10 to 12 percent salt, and never under 5 percent. Finished kimchi sits at 1.6 to 1.8 percent salt. At a room temperature of 18 to 22 °C the pH should fall to 4.6 or lower within 48 hours, and a batch that has not got there within 72 hours is discarded. Fermenting colder, at 10 °C or below, the same drop should come within 4 days, with 7 days as the limit. Finished kimchi is stored at 4 °C or colder.

Home cooks rarely own a pH meter, so Colorado State University’s extension service puts the home version in plainer terms: about 20 °C (68 °F) is ideal for a room-temperature start of one to two days, the kimchi should be packed tightly and kept pressed down to limit contact with air, and a batch with mould on the surface is thrown away.

What does kimchi taste like

Salty and sour first, then the chilli, then a savoury depth from the salted seafood. Young kimchi is crisp and only lightly sour. With time in the fridge it softens and sharpens, and past a certain point, as Oregon State University’s extension service puts it, it smells and tastes very vinegary. That over-fermented stage is not spoilage. It is the kimchi Koreans cook with.

Is kimchi spicy?

The red cabbage kind is, and the amount of gochugaru in the paste sets how much. The recipe above uses 2 cups for 2.7 kg of cabbage, and nothing stops a cook from using less.

Several kinds have no chilli at all, baek kimchi and dongchimi among them (both below). If heat is the problem, those two are a better answer than a timid red one.

The kinds worth knowing

Baechu kimchi

Napa cabbage kimchi, the recipe above.

Kkakdugi (radish kimchi)

Korean radish cut into cubes and seasoned with the red paste.

Oi sobagi

Cucumber kimchi, the cucumbers split and stuffed with seasoning. It is often confused with oi muchim, which is a quick seasoned cucumber salad rather than a fermented kimchi.

Baek kimchi

White kimchi, made without chilli pepper.

Dongchimi

Radish in a clear brine, non-spicy and watery.

Is there vegan kimchi?

Not by default. Standard recipes, including Maangchi’s, season with fish sauce and salted shrimp. The exception is old: Korean temple kimchi is made without garlic, scallions or jeotgal, because Buddhist monastic cooking avoids the onion family and animal products. Shop-bought vegan kimchi exists, and the ingredient list is the only reliable way to tell.

How long does kimchi last in the fridge?

The sources disagree, because they are measuring different things. Colorado State University advises eating home-made kimchi within a week for best quality. Korean Bapsang says it is at its most delicious for a couple of months and lasts much longer while it turns very sour. Oregon State University says it keeps in the fridge for months. The BC Centre for Disease Control’s guideline for producers works with best-before dates of about two months. All of them assume it is kept cold and covered.

Many Korean households use a kimchi refrigerator, a separate appliance built to hold fermenting kimchi at a steady low temperature.

Can kimchi go bad?

Yes, but sourness is not the sign. Bubbles and a sour smell are what fermentation looks like. Mould on the surface means the batch goes in the bin, and so does kimchi that has turned soft and slimy, which Oregon State University names as a sign of spoilage.

Is kimchi healthy?

It is a fermented vegetable, which is why it is often filed under probiotic foods. The figure worth knowing is the salt. At the 1.6 to 1.8 percent the BC Centre for Disease Control gives for finished kimchi, every 100 g carries roughly 1.6 to 1.8 g of salt, and that matters for anyone watching their sodium.

What to eat with kimchi

In Korea it is banchan: a small dish that stays on the table for the whole meal next to rice, soup and everything else. Our guide to how a Korean table works covers where it sits.

Old, sour kimchi goes into cooking. It is the whole point of kimchi jjigae, it is chopped into the filling of kimchi mandu, and aged kimchi is the third element of samhap, next to fermented skate and boiled pork. Gochugaru is also the chilli in gochujang, the fermented paste that makes the sauce for tteokbokki.

Kimjang, and why UNESCO listed it

In 2013 UNESCO inscribed kimjang, the making and sharing of kimchi, on its list of the intangible cultural heritage of humanity. The listing describes a year-long cycle: seafood bought for salting in spring, sea salt for the brine in summer, red chillies dried and ground in late summer, then in late autumn whole communities making enough kimchi to see every household through winter. It notes that family methods are typically passed from a mother-in-law to her newly married daughter-in-law.

South Korea’s Cultural Heritage Administration went further in November 2017 and designated kimchi damgeugi, kimchi making in general, as a national intangible cultural heritage item. That designation covers every kind of kimchi made across the peninsula, rather than the winter event alone.

Before it was red

Fermented vegetables are old in Korea. The Samguk Sagi records jars for fermenting vegetables in the Three Kingdoms period. The chilli is not old: it reached Korea as a New World crop, the first mention of it is in the encyclopedia Jibong yuseol of 1614, and chilli only became a widespread kimchi ingredient in the 19th century. The chilli-free kinds above are the older shape of the dish, not a modern concession to people who dislike heat.