Fermented Pastes: Gochujang, Doenjang, Miso, and How to Use Them

A fermented paste is not a seasoning but a finished ferment

Salt adds one thing. Sugar adds one thing. A paste does not. Soy protein broken down over months or years arrives with amino acids (savour), sugars (sweetness), organic acids (acidity) and salt already bound together in one substance.

So adding paste is not seasoning, it is adding another ingredient. You correct after it goes in, and if you finish the seasoning before it goes in the dish will be salty (fermentation basics, building umami).

Brands differ in salt, so season last

This is the most practical item on the page. Approximate ranges:

• Gochujang — 4-7% salt, and quite sweet
• Doenjang — 10-13% salt
• Miso — 5-13% salt (white low, red high)
• Doubanjiang — 10%+, with wide variation between products

The same "two tablespoons of doenjang" can differ by 2g of salt between brands, and in a soup you taste that difference directly. So the order is always: dissolve the paste, simmer, then decide about salt (salt and seasoning).

Paste scorches

A paste carries sugars and amino acids together, which is an ideal composition for the Maillard reaction — and that also means it burns easily. Dropped straight into a hot pan it turns bitter within seconds.

Two ways to handle it.

• Slacken it in liquid first. Hold the paste in a ladle, add a little of the broth, work out the lumps, then stir it in. This is the standard method for doenjang-jjigae.
• Fry it in oil. This is deliberately courting the Maillard reaction, and the condition is low heat, briefly.

Chunjang and doubanjiang must be fried

This looks like an exception to the rule above and is a separate matter. Unfried chunjang is bitter and astringent.

Frying the black bean paste in oil to drive that astringency off is half of making jjajangmyeon. Doubanjiang is the same: frying it until the oil runs red in mapo tofu is where the aroma comes from (blooming spices).

The window is low heat, thirty seconds to a minute, until the colour deepens slightly and the smell lifts. Over high heat that window does not exist.

Miso must not boil; doenjang has to

Two soybean ferments, opposite instructions, and the difference comes from how they are made.

• Miso is often fermented for a comparatively short time, and its aroma compounds and live enzymes are part of the flavour. Boiling drives those off. In miso soup the paste goes in after the heat is off.
• Doenjang is fermented far longer, its soy protein is more thoroughly broken down, and it needs to boil for that savour to move into the broth. A briefly simmered doenjang stew tastes shallow.

"Never boil fermented paste" is advice that is only true of miso.

Gochujang is not the heat

A common misconception with visible consequences. Gochujang is sweet, savoury and red — it is high in sugar. Most of the heat in a Korean dish comes from gochugaru, the chilli flakes (chilli and heat).

So adding more gochujang does not make a dish hotter, it makes it sweeter and thicker. Tteokbokki that is sweet but not spicy, jeyuk-bokkeum that tastes cloying — usually this. Reach for gochugaru when you want heat and gochujang when you want colour and body.

The sauces for bibimbap and golbaengi-muchim are built the same way: gochujang for the base, gochugaru to set the heat.

Cheonggukjang follows different rules

Cheonggukjang is fermented briefly — two or three days — and without salt, which makes it the outlier. With almost no salt of its own you season it separately, and its aroma compounds are heat-sensitive, so long boiling removes the very smell that defines it. Add it at the end and bring it to one boil.

Storage

• Press cling film onto the surface to exclude air, and refrigerate. A dry surface oxidises.
• White growth is usually yeast. Scrape it off and carry on.
• Black, red or green mould means throw it out.
• A surface darkening to brown is oxidation rather than spoilage, but the flavour in that layer has already gone.

Substitution changes the direction of the dish

• Miso for doenjang works, but the salt level and the depth of savour differ. Use slightly more and simmer it less.
• Miso + gochugaru + sugar for gochujang imitates the colour and sweetness, and only that.
• Gochujang for doubanjiang does not work. Doubanjiang is salty with a sharp fermented edge; gochujang is sweet, and the dish tips entirely toward sweetness.