At the heart of Hoisin Sauce lies a naturally fermented soybean paste. Soybeans, wheat flour, salt, and water are combined and inoculated with Aspergillus mould, then slowly aged over several months at a warm temperature. During this process, the proteins in the soybeans are broken down into natural amino acids, producing a deep umami flavour and a rich dark brown colour.
Lee Kum Kee (李錦記), founded in Hong Kong in 1888, is a brand that has crafted authentic Cantonese sauces across five generations. Sugar, garlic, chilli, spices, and sweet potato starch are added to the fermented soybean paste base to complete the distinctively rich and smooth flavour that defines Hoisin Sauce.
To draw a familiar European comparison — just as cheese gains depth by slowly transforming the proteins in milk over time, and sauerkraut develops new flavour by naturally fermenting cabbage, Chinese fermented soybean paste slowly transforms the proteins in soybeans to create an umami character that cannot be replicated. Think of it as the complex flavour of aged balsamic vinegar combined with miso paste.