Aromatic bases & spice pastes
Doubanjiang
豆瓣酱 · A thick, reddish-brown fermented paste of broad (fava) beans and erjingtiao Sichuan chili peppers, salted and aged in open clay crocks under the sun for at least several months. It functions as a reusable aromatic-and-seasoning base — not a finished dish — supplying the foundational salty, umami, and fruity-chili backbone of Sichuan cookery.
The formula
broad beans : erjingtiao chilies ≈ 1:2 by weight; salt 15–22 g per 100 g finished paste
Bean and chili cultures are built up separately with wheat-flour koji, then combined and sun-aged together; target moisture ~56% during fermentation.
Identity
- Fermented chili-bean paste from Pixian (Pi County), Sichuan
- Reusable aromatic base / seasoning foundation, not a finished dish
- Sun-aged in open clay crocks for a minimum of 3 months (often 6–12+ months, sometimes years)
- Visible intact broad-bean cotyledons and chili skin fragments suspended in a dark red paste
- Defined by salty, deeply umami, and fruity-chili flavors with fermented funk
- Wheat-flour koji stage used to develop mold cultures before salting
Ingredients
| Base | Dried broad beans (fava beans) | Steamed until tender; the structural and umami backbone of the paste. |
| Flavor | Erjingtiao (二荆条) chili peppers | Sichuan variety prized for bright red color and fruity rather than punishing heat; traditionally salted and pre-fermented before mixing. |
| Culture | Wheat flour (koji substrate) | Inoculates the beans with Aspergillus-type mold to build the broad-bean culture (豆瓣曲) before salting. |
| Seasoning | Uniodized salt | Added at 15–22 g per 100 g of finished paste to select for halophilic fermentation and prevent spoilage. |
| Liquid | Water / bean-steaming liquor (target ~56% moisture) | Maintains the semi-wet mash needed for the long salt-tolerant fermentation. |
Method
- 1Soak and steam dried broad beans until fully tender, then drain and cool to lukewarm.Hydrates the beans so the flour-borne mold can colonize them evenly without cooking off the culture.
- 2Mix the warm beans with wheat flour and spread in a thin layer to develop the broad-bean koji (豆瓣曲) for 5–7 days at ~28–32 °C, until bound in a yellow-green mold mat.Aspergillus-type molds break the beans' proteins and starches into amino acids and sugars that will become deep umami later.
- 3Meanwhile, salt the chopped erjingtiao chilies and let them stand until they develop their own lactic/yeast fermentation (辣椒曲).Pre-fermenting the chilies separately builds fruity, rounded chili flavor and a culture compatible with the bean koji.
- 4Combine the bean koji and chili culture, add the remaining salt to the target 15–22 g/100 g ratio, and mix to a uniform mash at roughly 56% moisture.Salt selects for halophilic microbes, stabilizes the mash for open-vat aging, and integrates the two cultures.
- 5Pack into shallow open clay crocks and sun-age for a minimum of 3 months (commercial Pixian styles 6–12+ months), turning or stirring periodically and raking the top crust.Day–night Sichuan temperature cycling and UV drive slow enzymatic and microbial conversion that creates the signature color, aroma, and mellowed heat.
- 6Seal the aged paste under a layer of oil or transfer to jars once the desired color (deep brick-red) and aroma (salty-umami with fruity chili) are reached.Stops further fermentation and protects the paste from surface spoilage for long storage.
Techniques that matter
Two-stage koji (bean culture + chili culture)
Lets protein-rich beans and sugar-rich chilies each be colonized by the microbes best suited to them before being united under salt.
Open-vat sun aging in clay crocks
Uses Sichuan's strong diurnal temperature swings and humidity to drive slow, mixed-culture fermentation without sealed anaerobic spoilage.
Salt-controlled semi-dry mash (~56% moisture, 15–22% salt)
Selects for salt-tolerant lactic and yeast activity while suppressing pathogens in a paste, not a brine.
Variations & derivatives
Pixian doubanjiang (郫县豆瓣酱)Pixian/Pi County, Sichuan
The benchmark style: 6–12+ months of sun aging, deep red-brown, and the version most recipes call for.
Short-cut home doubanjiangWestern home kitchens
Compresses aging to 3–6 weeks using warm incubation; lighter color and less depth but serviceable.
Chengdu-style doubanjiangChengdu, Sichuan
Often includes a fraction of soybeans alongside broad beans for a slightly sweeter, rounder profile.
Used in these dishes
Substitutions
- Authentic aged Pixian doubanjiang → Korean gochujang — Shares fermented-chili-bean umami but is sweeter, glutinous-rice-bound, and lacks doubanjiang's salty-savory dryness.changes result
- Erjingtiao chilies → Other medium-heat red Sichuan chilies (e.g., chao tian jiao) — Acceptable for color and heat; loses some of erjingtiao's characteristic fruity fragrance.
- Broad (fava) beans → Soybeans alone — Yields a softer, sweeter paste closer to yellow soybean paste; the signature intact-bean texture and flavor are lost.changes result
Troubleshooting
Paste smells sharply acidic or vinegary
Moisture too high or salt below target, allowing uncontrolled lactic over-fermentation → Blend in additional salt and a handful of aged paste as a back-slop to reseed a balanced culture, then resume covered aging.
Surface turns black or develops foul mold
Open crock exposed to contaminated air or aged paste not sealed under oil after aging → Scrape off and discard the top 1–2 cm; in future, seal finished paste under a thin layer of oil once the desired flavor is reached.
Color stays pale brown instead of deep red
Insufficient sun aging time, low-quality/non-erjingtiao chilies, or too little chili-to-bean ratio → Extend sun aging and verify chili variety and ratio (should sit near 2:1 chili:bean by weight).
Paste is overly salty and one-dimensional
Salt dosed above 22 g/100 g of finished paste, halting enzymatic development → Use less salt in the next batch and/or extend aging so proteolysis and chili-derived sugars balance the salt.