1/8 teaspoon ale yeast (also called brewer’s yeast)
Split vanilla bean in half lengthwise. Place vanilla bean, roots, and spices in a medium saucepan filled with 2 quarts (8 cups) of the distilled water, and bring to a boil over high heat. Reduce heat and simmer mixture, uncovered, for about 15 minutes. Stir in sugar, molasses, and orange zest, and continue to simmer for 10 minutes more, stirring often until sugar is completely dissolved. Remove from heat and let steep for 30 minutes.
Pour remaining 1 quart (4 cups) of distilled water into the clean glass jug. Line a fine mesh strainer with several layers of rinsed cheesecloth. Set the strainer inside the large funnel, and strain root mixture into the jug. Place the cap on and allow mixture to cool, aiming for a lukewarm temperature (about 70°F to 75°F). This will take several hours. Once mixture is cooled, shake vigorously.
Combine yeast and 1/4 cup warm water in a small bowl. Let sit about 5 minutes. Add yeast liquid to the jug through the funnel, screw the cap back on, and shake vigorously. Now you’re ready to bottle the root beer.
Place the 4 filled and sealed bottles and the test bottle upright in a cool spot at room temperature (about 70°F to 75°F) to ferment (we found that the bathtub is ideal).
After about 48 hours, check the carbonation by sampling your test bottle. If it’s sufficient, place labels on the bottles and refrigerate them to halt the fermentation process; if not, let them sit for another day. We found that 3 days was perfect each time.