Waterloo Watermelon Sparkling Water Recipe

Prepare watermelon juice

If using fresh watermelon, cut a small chunk (about 1/2 cup), remove rind and seeds, and purée in a blender until smooth. Strain the purée through a fine mesh sieve or cheesecloth to yield approximately 2 tablespoons of clear watermelon juice.

Chill 12 oz of filtered sparkling water so it is cold (around 38°F / 3°C). Cold water holds carbonation better and prevents excessive foaming when flavoring.

In a small chilled measuring cup, combine the 2 tablespoons of strained watermelon juice with 2 teaspoons of watermelon essence (natural flavor concentrate). Stir gently to blend.

Slowly add the flavored concentrate to the chilled sparkling water by pouring down the side of the glass or can in a thin stream to minimize CO2 loss. Stir very gently once or twice with a sanitized spoon to distribute flavor without releasing much gas.

Add 1 teaspoon fresh lime juice to the sparkling water mixture to brighten the flavor. If you prefer a slightly sharper profile or if the watermelon tastes flat, dissolve 1 teaspoon citric acid in the lime juice before adding. Stir gently to combine.

If preparing for extended shelf life in a can, add a very small measured amount of potassium sorbate solution (approx. 0.1% final concentration). For a 12 oz can this is roughly 0.2 tsp of a pre-diluted solution—consult food-safety tables or a beverage technologist to achieve accurate preservative concentration. Add 0.25 tsp vegetable glycerin if a slightly fuller mouthfeel is desired. Mix gently and avoid agitation to preserve carbonation.

If serving immediately from a glass rather than can, garnish with a thin watermelon wedge and a mint sprig. Do not garnish inside a sealed can.