Koji

Koji is a culinary ingredient made from rice, barley, or soybeans that have been cultivated with a specific mould, typically *Aspergillus oryzae*. This fermentation process breaks down starches and proteins, creating unique enzymes that are essential for producing many traditional East Asian foods. It has a savoury, umami-rich flavour profile.

Koji is primarily used as a starter culture in the production of fermented foods like soy sauce, miso, and sake. It acts as a natural flavour enhancer, tenderiser, and can contribute to the browning and sweetness of foods through enzymatic activity. Manufacturers use it to develop complex, savoury flavours and improve the texture of products such as marinades, sauces, and cured meats.

Koji itself is not typically considered a food additive under UK law; it is a fermented ingredient. Foods containing koji are subject to general food safety regulations. While fermentation processes can produce a range of compounds, there are no specific health concerns associated with the typical consumption of foods where koji is used as a traditional ingredient. Regulatory bodies have not set specific limits for koji as an ingredient.