Sichuan Doubanjiang (Chilli Bean Paste): The Soul of Sichuan

Pi county (now Pixian) in Sichuan province has been the production centre for the most highly regarded doubanjiang for centuries — the Pi county variety is considered the benchmark, its quality coming from the specific Sichuan chilli varieties, the locally made broad bean paste, and a multi-year fermentation process (premium versions are aged 3–5 years). The result: a paste of extraordinary depth, with a brick-red colour, a pungent, fermented aroma, and a complex flavour of chilli heat, fermented bean savouriness, and a slightly sweet background.

Doubanjiang — fermented broad bean and chilli paste — is the foundational flavouring of the Sichuan kitchen. More than any other single ingredient, doubanjiang defines the aromatic and flavour profile of Sichuan cooking: its deep, complex, fermented savouriness; its chilli heat; its aromatic richness. Dunlop describes it as the soul of Sichuan cooking and the ingredient without which many of the tradition's most important preparations cannot be made. A pot of quality doubanjiang in the refrigerator is the beginning of the Sichuan kitchen.

Doubanjiang's flavour chemistry combines fermented broad bean's glutamic acid (umami foundation), the chilli's capsaicin (heat), the chilli's carotenoid pigments (colour and flavour), and the complex Maillard products of the fermentation (a range of volatile compounds including aldehydes, ketones, and esters). When fried in oil, the fat-soluble carotenoids and capsaicin carrier molecules dissolve into the oil phase, while the water-soluble glutamic acid compounds remain in the paste — the combination of fat-carried and water-carried flavour compounds distributes through the entire dish as both a liquid and a fat component.