Sweet Potato Fly

    timeframe: 3 days

    Both Nourishing Traditions and Wild Fermentation describe the effervescent fruity tones of sweet potato fly, a soft drink from Guyana. An interesting point to this recipe is that the eggshell neutralizes the acidity of the fermentation and helps to reduce oxalates.


    • 1 tsp mace
    • 2 sweet potatoes large
    • 2 cups granulated sugar or honey
    • ½ cup whey
    • 2 lemons
    • 1 pinch cinnamon
    • 1 pinch nutmeg
    • 1 eggshell, boiled to sterilize


    • large mixing bowl
    • mason jars
    • canning funnel (optional)


    1. Boil 1 cup of water with mace. Remove from heat and allow to cool.

    2. Grate the sweet potatoes and rinse well through a strainer to remove the starch.

    3. Grate lemon peels and juice. Boil and crush eggshell.

    4. In a large bowl, combine all ingredients in a gallon of water. Add the cooled mace.

    5. Stir, cover to keep dust and flies out, and leave in a warm spot to ferment for about 3 days.

    6. Strain into storage containers, keep refrigerated, and serve chilled. Lasts for months.


    Sweet potato fly

    Food Chemistry

    The calcium carbonate in the eggshell dissolves in the lemon juice to form calcium citrate, which binds to the oxalates in the sweet potatoes, making them safer to consume!