Clean the pineapple: Wash the pineapple thoroughly, scrubbing the skin well. Carefully peel the pineapple, reserving the rinds and core. You can use the flesh for another purpose. Cut the rinds into large pieces.

Combine ingredients: In a large, clean glass jar or pitcher (at least 1-gallon capacity), combine the pineapple rinds and core, piloncillo (or brown sugar), cinnamon sticks, cloves, and salt (if using).

Add water: Pour in the filtered water, ensuring all the pineapple rinds are submerged. You may need to use a clean weight (like a smaller jar or a fermentation weight) to keep them under the liquid.

Cover and ferment: Cover the jar opening with a clean cloth or cheesecloth, secured with a rubber band. This allows air circulation while keeping out contaminants. Place the jar in a warm spot (ideally 70-80°F / 21-27°C) away from direct sunlight.

Monitor fermentation: Let it ferment for 2-4 days. You should start seeing small bubbles rising to the surface, especially when you gently tap the jar. A thin layer of white foam or scum may form on top; this is normal kahm yeast. Skim it off if desired. Taste daily after day 2. It should be slightly sweet, tangy, and fizzy.

Strain and bottle: Once it reaches your desired flavor and fizziness, strain the tepache through a fine-mesh sieve or cheesecloth into clean bottles. Leave some headspace in each bottle if you plan to secondary ferment for more fizz.

Secondary fermentation (optional): Seal the bottles tightly and let them sit at room temperature for another 12-24 hours to build more carbonation. "Burp" the bottles occasionally by opening them briefly to release excess pressure, preventing explosions.

Chill and enjoy: Transfer the bottled tepache to the refrigerator. Chilling will slow down fermentation and prevent it from becoming too alcoholic or vinegary. Enjoy cold!