Tamarind — a tangy, tart fruit pod used as the primary souring agent in sinigang and other sour Filipino soups.
Sampalok gives sinigang its signature sour edge — a flavor Filipinos describe as "maasim," distinct from the sourness of vinegar or citrus. Fresh tamarind pulp, boiled and strained, is the traditional base, though most households today reach for powdered sinigang mix or tamarind soup base for convenience.
Tamarind isn't the only souring agent in Filipino cooking — green mango, kamias (a small sour fruit), and calamansi all show up as regional or personal variations — but sampalok is the most iconic, and the one most associated with sinigang specifically.
Recipes on Pancit.com that call for sampalok.
Tamarind-soured Filipino pork soup with vegetables — a comfort-food classic.
Chicken simmered in a clear ginger broth with green papaya and chili leaves.