Is there a homemade vegetarian substitute for fish sauce?
Fish sauce is rich in glutamates, tastebud stimulators that give food the meaty, savory flavor known as umami. Glutamates are often found in animal proteins, and in the case of fish sauce, they come from fermented fish.
Knowing that seaweed is a potent (and vegetarian) source of glutamates, we optimistically tried subbing a strong salted kelp broth for fish sauce in a Thai dipping sauce. When it failed to contribute sufficient depth, we turned to another source of savory flavor: nucleotides.
When flavor-boosting nucleotides are paired with glutamates, the perception of umami is significantly increased. Sure enough, a salty broth made with dried shiitake mushrooms (rich in nucleotides) and soy sauce (glutamates) provided just the right meaty punch as a 1:1 substitute for fish sauce. Here’s how to make it: