If you have ever cooked Asian food and ended up with a disappointing result, the culprit might be your choice of soy sauce. Despite the ubiquity of brands like Kikkoman, not all soy sauces are created equal, and using the wrong one can drastically alter a dish.
Soy sauce originated over 2,000 years ago during the Han dynasty, when a singular fermented condiment made from fish and soy split into fish sauce and soy sauce. The latter was taken to East Asia by Buddhist vegetarians, while Chinese merchants introduced both to Southeast Asia. This historical divergence explains why fish sauce dominates in Southeast Asian cuisine, while soy sauce is more common in Chinese-influenced dishes.
The production of soy sauce varies by region, influenced by factors such as the type of mold used (e.g., Aspergillus oryzae), the presence of wheat, aging time, and ingredient ratios. For example, Japanese koikuchi is a dark, all-purpose soy sauce, while tamari is a wheat-free byproduct of miso making. Light soy sauce is thinner and saltier, ideal for seasoning and dipping, whereas dark soy sauce, often from Taiwan, includes rock salt and is used for red cooking.
In the UK, only two soy sauces are considered authentic: Kikkoman koikuchi and a premium light soy sauce. Other varieties, such as Thai dark sweet soy or Indonesian kecap manis, are essential for specific dishes like pad see ew or satay but are not widely available in standard supermarkets. For best results, match the soy sauce to the dish's cultural origin, as substituting can lead to off flavours.
