Background
The objective is to produce a garum from tempeh to leverage umami synergy. Synergistic umami relies on pairing free glutamates with nucleotides such as IMP and GMP, which are typically concentrated in animal products, yeast, and shiitake mushrooms.
During tempeh fermentation, the mold produces small amounts of IMP and GMP. When combined with the enzymatic breakdown from koji (releasing free amino acids/glutamates), this should theoretically yield significantly more umami depth than using raw or cooked grains alone.
Formula
Ingredients
- 1,636 g Wheat and oat tempeh
- 1,636 g rye koji
- 3,272 g Water (1:1 ratio to total solid substrate)
- 5% Salt by total mass of the mixture (solids + water)
Notes and Observations
- Incubation: Held for 1 month at 60°C.
- Tasting Notes: Richer profile than a standard wheat or grain shoyu. While not quite as heavy or deep as a soy-based amino sauce, it has a distinct, complementary richness with more body. Carries a touch more funk, but remains very approachable. It could make an effective blending component with soy-based ferments.
Future Adjustments
- Tempeh mold (Rhizopus) may not be the most efficient nucleotide producer for this application. Research suggests certain Placidia mycetes species yield significantly higher levels of IMP and GMP; running a subsequent trial with those cultures could amplify the umami effect substantially.