Introduction

Mukeunji (묵은지) means “old kimchi”: napa cabbage kimchi that has been fermented for many months, often a year or longer, in a cold kimchi refrigerator or a traditional onggi jar. As it ages it turns soft, deeply sour and full of savory flavor. Koreans rarely eat it as a fresh side dish; instead it is the secret to the best kimchi jjigae, braised kimchi with pork and rinsed kimchi wrapped around rice. Restaurants that specialize in mukeunji dishes are popular all over Korea.

Mukeunji at a Glance

Quick facts

• What it is: long-aged napa cabbage kimchi, usually 6 months to several years old
• Main ingredients: salted napa cabbage, gochugaru, garlic, ginger, fish sauce or salted seafood
• Taste: very sour, savory, less spicy than fresh kimchi, soft but still slightly crunchy at the stem
• Main uses: kimchi jjigae, kimchi jjim, kimchi fried rice, mukeunji ssambap

What is Mukeunji Made Of?

Mukeunji starts as ordinary whole-cabbage kimchi, usually made during the late-autumn kimjang season. For long aging, cooks salt the cabbage a little more heavily and use less sugar and fruit, then pack it tightly so it stays submerged in its own brine. Kept very cold, it ferments slowly; lactic acid bacteria keep producing acid, and the cabbage softens and develops rich, complex savoriness.

Types of mukeunji

• Sin-kimchi (sour kimchi): a few weeks to months old, already good for stew.
• Mukeunji: aged roughly 6 months or more, very sour and soft.
• Long-aged mukeunji: 1–3 years, sold as a premium product.
• White mukeunji: rinsed or non-spicy aged kimchi used for wraps and braises.

What Does Mukeunji Taste Like?

Straight from the jar it is sharply sour and salty, with a funky, wine-like depth. Once cooked, the sourness mellows and the cabbage melts into the broth, giving stews a rich, tangy body that fresh kimchi cannot match. The chili heat fades over time, so mukeunji often tastes less spicy than younger kimchi.

Popular Korean Dishes That Use Mukeunji

Dwaeji kimchi jjigae

Pork and aged kimchi stew, the most classic use. Recipe below.

Mukeunji jjim

Whole aged kimchi leaves slowly braised with pork belly or mackerel until soft.

Mukeunji ssambap

Rinsed aged kimchi leaves wrapped around rice, seasoned with sesame oil.

Kimchi bokkeumbap

Sour kimchi makes the tastiest kimchi fried rice.

Easy Pork Kimchi Jjigae Recipe (Serves 2–3)

Ingredients

• 2 cups (about 300 g) mukeunji or very sour kimchi, cut into bite-size pieces
• 1/4 cup kimchi brine
• 7 oz (200 g) pork belly or pork shoulder, sliced
• 1/2 onion, sliced
• 1/2 block (7 oz / 200 g) firm or medium tofu, sliced
• 2 1/2 cups (600 ml) water, rice-rinsing water or anchovy stock
• 1 tbsp gochugaru
• 1 tsp minced garlic
• 1 tsp sugar (balances the sourness)
• 1 tsp sesame oil or neutral oil
• 1 green onion, sliced

Instructions

1. Heat the oil in a pot over medium heat. Add the pork and stir-fry for 3–4 minutes until no longer pink.
2. Add the kimchi, sugar and gochugaru and stir-fry 3–5 minutes, until the kimchi softens and smells toasty.
3. Pour in the water or stock and kimchi brine, add the garlic and onion, and bring to a boil.
4. Reduce to medium-low and simmer, covered, for 20 minutes so the aged kimchi turns tender and the broth deepens. Make sure the pork is fully cooked through.
5. Add the tofu and green onion and simmer 3 more minutes. Taste and add a little salt or fish sauce if needed. Serve bubbling hot with rice.

Tip: If your mukeunji is extremely sour, rinse half of it briefly under water or add an extra pinch of sugar.

Where to Buy Mukeunji

United States

As an Amazon Associate, I earn from qualifying purchases.

Amazon
Search Korean aged kimchi on Amazon
Search napa cabbage kimchi on Amazon

H-Mart
Search aged kimchi on H-Mart

Canada

Search Korean kimchi on Amazon.ca

Europe

Search Korean kimchi on Amazon.co.uk

How to Store Mukeunji

Keep mukeunji in an airtight container in the coldest part of the refrigerator, pressed down so the cabbage stays under the brine. Always use clean utensils. Some white film (kahm yeast) can form on old kimchi; discard the kimchi if you see fuzzy or colored mold, or if it smells rotten rather than sour. To make your own, simply keep a batch of kimchi very cold (around 32–34°F / 0–1°C) for several months.

Mukeunji FAQ

How old does kimchi have to be to be mukeunji?

There is no strict rule, but most Koreans call kimchi mukeunji after about 6 months of aging, and premium versions are aged a year or more.

Is mukeunji safe to eat?

Yes, when it has been kept cold and submerged in brine. Its high acidity and salt help preserve it. Throw it away if it develops mold or an off smell.

Can I use regular kimchi for kimchi jjigae?

Yes, but fresh kimchi makes a flatter stew. If your kimchi is young, add a splash of rice vinegar and simmer longer.

Why is mukeunji less spicy?

During long fermentation the sourness becomes dominant and the chili heat seems to fade, so the overall taste is tangy rather than fiery.

Conclusion

Mukeunji is patience in a jar: the older and sourer it gets, the better your stews become. Use it in the pork kimchi jjigae above, or try a quick pantry version with our tuna kimchi jjigae. For a fresher kimchi to eat on the side, see kkakdugi.