Can You Coagulate Tofu Without Nigari?
We tested five alternative coagulants against traditional nigari, scoring each on yield, texture, and flavor neutrality. One surprised us.
Nigari — magnesium chloride, traditionally derived from seawater — is the standard coagulant for firm tofu. It works well. It's also not the only option, and we wanted to know what tradeoffs the alternatives actually carry.
Coagulants tested
We ran identical soy milk batches through five coagulation methods: traditional nigari, food-grade calcium sulfate (gypsum), lemon juice, white vinegar, and Epsom salt (magnesium sulfate).
Results
Gypsum produced the highest yield by a meaningful margin and a notably smoother, more delicate curd — the method most commonly used in Chinese-style silken tofu production, and for good reason.
Lemon juice and vinegar both worked but introduced a faint acidity that lingered even after rinsing, which limits their use to recipes where that flavor note is welcome.
Epsom salt performed closest to nigari in both texture and neutrality, which tracks — chemically, it's a close cousin. If nigari isn't available, this is our recommended substitute.
Still to test
We haven't yet tried GDL (glucono delta-lactone), which is common in commercial silken tofu production and deserves its own dedicated round.