Watermelon Slushie with Ninja Slushi

With its high water content, watermelon is the ideal fruit for creating a refreshing drink without having to add crushed ice to the Ninja Slushi. I love using this naturally sweet base, but the texture requires a little vigilance. Since watermelon is almost exclusively composed of water, a dash of syrup is essential to prevent the mixture from turning into a block of ice in the tank. By balancing the ratios well, you get a perfectly smooth, ultra-fresh result with a delicate fragrance, ideal for sipping on hot days.

Watermelon Slushie with Ninja Slushi

Recipe by Camille Roos

0.0 from 0 votes

Course: Slush / GranitaCuisine: Difficulty: Easy

Servings

4

people

Prep

10

minutes

Freeze time

45

minutes

Total time

55

minutes

Watermelon is the ideal fruit for creating a refreshing drink without crushed ice with Ninja Slushi. A splash of syrup ensures a smooth and perfectly drinkable texture with a straw.

Ingredients

• 800 g watermelon flesh (ideally seedless)

• 1 lime (juice)

• 2 tablespoons agave syrup (or cane sugar syrup)

• 50 ml water (only if needed to help blending)

Instructions

• Blend the chopped watermelon flesh with the lime juice and agave syrup. Added sugar controls the crystallization of this very water-rich drink.
• Strain the mixture through a sieve to remove thick fibers and any seeds. This step makes a slushie that is much smoother and more enjoyable to drink with a straw.
• Pour the resulting juice into the Ninja Slushi tank, ensuring the level is well between the min and max lines.
• Select the Slush program, let the machine churn until it reaches a slush consistency, then serve immediately.

Summer cocktail version (with alcohol)

Summer cocktail version (with alcohol) : Add 10 cl vodka or white rum to the tank and select the Frozen Cocktail program. (Alcohol abuse is dangerous for your health, consume in moderation).

The secret to a texture that doesn’t freeze into a block

When using a fruit very rich in water, the classic mistake is to skip sugar entirely, thinking you’re making a healthier drink. I often see this with summer juices: without a minimum amount of sugar, the machine will freeze your preparation into a rigid block, impossible to serve. For this recipe, agave syrup acts as a natural antifreeze. It allows the blades to keep churning the liquid while lowering the freezing point. If your fruit is sun-drenched and naturally very fragrant, you can slightly reduce the dose, but never omit it completely. By aiming for a sugar ratio of about 12%, you guarantee a result that stays flexible in the tank, ideal for sipping through a straw effortlessly. If you prefer other flavors, feel free to check out the watermelon mint granita with Ninja Slushi to vary the aromatic pleasures.

Why straining makes all the difference

At first, I tended to just blend the flesh and pour everything directly into the tank, thinking the fibers gave the drink more body. But after several trials, I realized the final result lacked finesse. Watermelon leaves small pulpy residues that often clog the straw or alter the mouthfeel. By passing the juice through a fine sieve before pouring it into your machine, you remove these impurities and any seeds that might have remained. This simple gesture transforms a rustic juice into a truly pleasant drink. Moreover, a clear liquid offers a much more consistent freeze, limiting the risks of seeing the machine lights flash due to pulp being too thick. To explore other refreshing variations, the watermelon granita with lime juice is also an excellent option.

Do you like adding a bit of fresh mint to your watermelon slushie?

Frequently asked questions

My preparation freezes too quickly and forms a block, what should I do?

This is a sign of a lack of sugar. Watermelon contains a lot of water, so it is imperative to add a little agave or cane syrup to soften the freezing process and obtain a slush.

Can I use frozen watermelon to save time?

It’s not necessary and it complicates the initial blending. Ninja Slushi cools room-temperature liquids very well, so always favor fresh fruit.

Which program should I choose if I add alcohol?

If you turn this recipe into an adult version with rum or vodka, switch to the Frozen Cocktail program to compensate for the antifreeze effect of alcohol, which requires more intense cold.