Fermentation
1 pineapple, with skin, top and bottom trimmed, cut into 1” pieces (about 10 cups)
1 cup turbinado sugar
1 cup palm sugar, chopped
3 tablespoons whole coriander seeds
1 tablespoon grains of paradise
6 long peppercorns
1 tablespoon cubeb pepper
Combine pineapple, turbinado sugar, palm sugar, coriander, grains of paradise, long peppercorns, cubeb peppers, and 8 cups warm water in a 4-quart container with a tight-fitting lid. Stir to combine, cover tightly, and set aside in a warm, draft-free area (about 75°F) until sugar is dissolved, mixture is slightly warmer than room temperature, and a little fizzy, 2-3 days. (Check after the 2nd day. If mixture isn’t ready, cover and let ferment another day).
Using a slotted spoon, skim the solids from the top of the container and discard. Strain mixture through a cheese-cloth-lined fine-meshed sieve into a 3-qt. container. Cover and let sit at room temperature overnight, then refrigerate.
DO AHEAD: Tepache can be made up to one week ahead.