Ganjang (Korean Soy Sauce)

Ganjang is the Korean word for soy sauce, and like Japanese shoyu, it is a fermented product made from soybeans and salt. But the similarity is deceptive: the Korean tradition produces soy sauces that diverge significantly from their Japanese counterparts in both flavor and use, and understanding the difference between the two main types is essential to cooking Korean food that tastes right.

The distinction that matters most is historical. Korean soy sauce traditionally developed as a byproduct of doenjang (fermented soybean paste) production — the liquid that separated off the top of fermenting soybean blocks was collected and aged into what is now called joseon ganjang. The result is a soy sauce with its own distinctive character, quite different from the Japanese molds-and-wheat fermentation process. Modern commercial Korean soy sauce developed separately, following a more Japanese-influenced method, and now dominates supermarket shelves across Korea and Korean grocery stores worldwide.

Flavor profile

Joseon ganjang (also called guk ganjang, soup soy sauce, or traditional Korean soy sauce) is intensely salty, dark, and slightly funky in a way that Japanese soy sauce is not. It has a stronger fermented character and less sweetness. The saltiness is its defining feature — it is used in small quantities to season rather than to flavor broadly.

Jin ganjang (commercial Korean soy sauce, brands Sempio 701 and Beksul being the most recognized) is much closer to Japanese koikuchi shoyu in color, viscosity, and flavor. It is slightly less sweet than Japanese soy but functions similarly in most applications. This is the soy sauce that Western recipes label "Korean soy sauce" and the one you will find in most Korean American home kitchens.

How to use it

Joseon ganjang belongs in soups and broths — specifically the clear, clean soups of Korean cuisine like miyeok-guk (seaweed soup) and kongnamul-guk (bean sprout soup). Its darkness would overwhelm stir-fries and would discolor delicate dishes. Use it in tiny amounts: a teaspoon or two per pot of soup is often enough.

Jin ganjang covers everything else: stir-fries, marinades, dipping sauces, braising liquids, and seasoned side dishes (banchan). It is the soy sauce in bulgogi marinade, in japchae sauce, and in the dipping sauce for Korean dumplings. Use it anywhere a recipe calls for soy sauce without specifying a type.

Buying guide

For jin ganjang, Sempio 701 is the benchmark — clean, balanced, widely considered the standard for Korean cooking. Beksul is a reliable second choice. Both are available at Korean grocery stores and online. Sempio 500 is a lighter-colored version better suited to dishes where you don't want the sauce to darken the food.

For joseon ganjang, look for bottles labeled guk ganjang or joseon ganjang. It is harder to find outside Korea but stocked by most Korean grocery stores that carry a serious pantry section.

Storage

Store at room temperature before opening. Once opened, refrigeration extends shelf life significantly — both types keep at room temperature for months but will last a year or more refrigerated. Look for a production date on the bottle; fresher is better.

The borderless angle

Jin ganjang substitutes seamlessly for Japanese koikuchi soy sauce in most recipes — the two are close enough that the swap goes unnoticed in dishes with multiple other flavors. Korean American fusion cooking leans on this interchangeability constantly, using jin ganjang in Japanese-inspired preparations and Japanese shoyu in Korean ones. Joseon ganjang, however, has no easy equivalent in the Japanese tradition; its closest functional analog in the broader soy world is Chinese light soy sauce, which shares the saltier, less-sweet character.