Someone taking the fermenting class was interested in Fermented Watermelon Rinds, so we gave it a try. We used a seedless watermelon. The rind was thin. I believe a seeded watermelon may have a thicker rind and be easier to peel.
Fermented Watermelon Rind Pickles Makes 1 quart
1 1/2 pounds watermelon rind (enough to fill a quart-size jar)
1 garlic clove, peeled and smashed
1 bay leaf
1/2 teaspoon black peppercorns
1/2 teaspoon coriander seeds
1/2 teaspoon dill seeds
1/2 teaspoon yellow mustard seeds
3 cups water (see Recipe Notes)
1 1/4 ounces (about 2 tablespoons) salt (see Recipe Notes)
Using a spoon, scrape away any remaining flesh from the watermelon rind. Carefully remove the outer green peel using a sharp knife or vegetable peeler. Cut the rind into 1-inch squares or other uniform shapes as desired.
Place the garlic, bay leaf, peppercorns, coriander, dill, and mustard in the bottom of a clean jar. Pack the watermelon rinds into the jar, leaving at least 1-inch headspace at the top of the jar.
Combine the water and salt to make a brine. Pour the brine over the rinds, ensuring that they are covered (you might not use all of the brine). Keep the rinds submerged by weighing them down with a fermentation weight or other clean objects such as a small jelly jar, a rock, or a brine-filled plastic bag. Cover the jar.
Ferment the rinds for 1 to 3 days at room temperature and away from direct sunlight. Taste them daily and transfer them to the refrigerator when they are to your liking. You may notice some bubbles as the rinds ferment; this is a good sign that the lactic acid bacteria are working.
Consume within 3 months. Discard if the pickles develop mold, slime, mush, or disagreeable odors.