1. Bring a 4-qt. saucepan of salted water to a boil, and add beets; cook until just tender, about 3 minutes. Drain and transfer to a bowl of ice water, and let sit for 2 minutes to chill. Drain and place beets in a sterilized 1-qt. glass jar along with mustard seeds, allspice berries, peppercorns, cloves, cinnamon, ginger, and orange peel. In a medium bowl, stir together whey, honey, and filtered water; pour over beets until covered. Pour any remaining brine or water into a resealable plastic sandwich bag, and place bag on top of beets to keep them submerged.
2. Drape a clean kitchen towel over the jar, and let it sit at room temperature until beets have cured to your taste, about 1 week. Season after curing with kosher or sea salt to taste, cover jar with lid, and refrigerate for up to 1 week.