The Art of Korean Fermented Soy Sauces - Cheongjang, Ganjang and Jinjang

Korean cuisine has long been synonymous with fermentation, a method that transforms simple ingredients into complex, flavorful foods. Among the stars of fermented Korean foods are jang—traditional soy sauces—that bring rich umami flavors to the table while also offering probiotic health benefits. In this post, we will explore the different types of jang—Cheongjang (청장), Ganjang (간장), and Jinjang (진장)—as described by Ki Soondo, the master of Jinjang. We’ll also compare these traditional sauces to the mass-produced varieties found on supermarket shelves.

Whether you're a curious home cook or interested in health-boosting foods, understanding jang will elevate your cooking and enhance your understanding of fermentation’s nutritional benefits and Korean cuisine in general.

The Benefits of Fermentation

Fermentation is a natural process where lactic acid bacteria break down sugars and starches, transforming them into beneficial compounds. Probiotics, which develop during fermentation, contribute to a healthy gut, improving digestion and bolstering the immune system. Korean soy sauces, especially when traditionally fermented over months or years, carry these probiotic benefits, helping to maintain good health.

According to Ki Soondo, the creation of soy sauces follows a seasonal rhythm that has been passed down through generations. Here’s how she explains the process:

• In the fall, freshly harvested soybeans are thoroughly cleaned and boiled before being mashed into blocks called meju.
• These blocks are then air-dried for about a month and fermented by hanging them up to allow natural bacteria to develop.
• In November, the meju blocks are placed in a brine solution for continued fermentation, and by January, the jang is ready to be mixed into the large pots that will age the sauces.

This time-honored method results in two primary products: ganjang (soy sauce) and doenjang (fermented soybean paste). After approximately 60 to 70 days, the soy sauce can be separated from the solid parts, leaving ganjang as the liquid and doenjang as the paste. The entire process takes at least 10 months, though longer aging creates deeper, richer flavors.

Exploring Cheongjang, Ganjang, and Jinjang

1. Cheongjang (청장) – Aged up to 1 Year

Cheongjang is typically fermented for up to a year. Its light flavor and color make it ideal for lighter dishes such as cucumber salads, bean sprout side dishes, or even a refreshing cold cucumber soup. According to Master Ki Soondo, cheongjang is perfect for dishes where a clean and subtle soy flavor is needed. While cheongjang doesn’t have the complexity of longer-aged soy sauces, it still offers the core benefits of fermented food—supporting gut health and nutrient absorption.

2. Ganjang (간장) – Aged 1 to 2 Years

Ganjang is a more versatile soy sauce, fermented for 1 to 2 years, and is commonly used for marinating, stir-frying, or even making bulgogi and japchae. Master Ki mentions that she uses ganjang for a variety of dishes, including soy sauce-based kimchi and stir-fried glass noodles. The extended fermentation period allows the ganjang to develop deeper umami notes, and its amber color reflects its complexity. Ganjang is often referred to as the backbone of Korean cooking, making it essential in any kitchen.

3. Jinjang (진장) – Aged 5+ Years

Finally, there’s jinjang, which is aged for five years or more. According to Ki Soondo, this is where the magic truly happens. The process involves aging the soy sauce in special pots for over a year, with further aging over four more years, resulting in an incredibly rich and umami-packed sauce. She describes jinjang as the ultimate soy sauce, used in special dishes like abalone stew or simply as a high-end finishing sauce. Jinjang has a dark, almost syrupy texture, and its flavor is unmatched—complex, savory, and slightly sweet.

The extended fermentation not only gives jinjang its superior taste but also enhances its probiotic content and nutritional benefits. As Ki Soondo puts it, jinjang isn’t just a soy sauce; it’s an experience. The depth of flavor is why she received her title as a master of jinjang, with each drop of this sauce bringing out the best in even the simplest of dishes.

How Large Companies Speed Up Soy Sauce Production

While traditional soy sauces like cheongjang, ganjang, and jinjang take months to years to ferment, modern manufacturing processes allow large companies to produce soy sauce in just weeks. Here’s how:

• Acid Hydrolysis: Large companies break down soy proteins with hydrochloric acid instead of letting them naturally ferment. This process, called acid hydrolysis, takes a matter of days rather than months.
• Flavor Enhancements: Because this method doesn’t develop the natural umami flavors of fermentation, manufacturers often add artificial flavors, sweeteners, and coloring agents to mimic the taste of traditionally brewed soy sauce. It doesn’t sound 

While these mass-produced soy sauces are convenient, they lack the complexity, health benefits, and probiotic content of the slow-fermented varieties following the wild fermentation method which is a Koreans tradition.

Why Traditional Fermentation Matters

When you choose traditionally fermented soy sauces, you’re not just opting for flavor—you’re also selecting a product that’s packed with nutritional benefits. The depth of flavor and richness of cheongjang, ganjang, and jinjang comes from the natural fermentation process, which can’t be replicated in a factory. The longer fermentation time allows probiotics to flourish and complex flavor profiles to develop, offering both taste and health benefits that are impossible to achieve through shortcuts.

Discover Premium Korean Soy Sauces at Kim'C Market