Step 1

Peel and finely grate the ginger (I use a Microplane). You should have about 2 tablespoons of grated gingerroot.

Step 2

Bring the water to a boil in a small saucepan on the stove top or in the microwave. Remove from the heat. Add the sugar and salt and stir to dissolve. Add the ginger and let stand until cool. Stir in the lemon juice.

Step 3

Pour the ginger water into a clean 2-liter bottle using a funnel. Do not strain out the ginger. Top off the bottle with water, leaving at least 1 inch of headspace. Give it a taste and add more lemon juice or sugar if desired. The extra sugar will dissolve on its own.

Step 4

Add the yeast. Screw on the cap and shake the bottle to dissolve and distribute the yeast. Let the bottle sit at room temperature out of direct sunlight until carbonated, typically 12 to 48 hours, depending on the temperature of the room. Check the bottle periodically; when it feels rock solid with very little give, it’s ready.

Step 5

Refrigerate overnight or for up to 2 weeks. Open very slowly over a sink to release the pressure gradually and avoid bubble-ups. Pour the soda through a small fine-mesh strainer to catch the ginger as you pour.