Here's What Happens If You Freeze Watermelon - Tasting Table
Briefly

Once sliced, watermelon lasts about four days in the refrigerator, so preservation options are useful. Cut the flesh into cubes or balls, remove seeds and rind, and single-layer pieces on a parchment-lined baking sheet to pre-freeze before transferring to a sealed freezer bag or container with some headspace. Frozen watermelon becomes slushy when thawed because of high water content, so it will not regain original crispness. The slushy texture works well in smoothies, slushies, and icy toppings. Freeze the slush in ice trays for cocktail or sparkling-water flavoring. Avoid freezing large chunks with rind. Frozen watermelon keeps six to twelve months.
Something's got to happen before that fading-fast cut melon gets squishy. Once sliced, watermelon only lasts about four days in the refrigerator, so time isn't on your side. Fortunately, there's some good news: It's absolutely possible to freeze watermelon. Granted, it's not wise to toss a big chunk, rind and all, into your freezer, nor would there be room to do so.
However, with time and some knife-carving patience, you can create a sweet and juicy future snack that's craveable and nutritious. This involves cutting the watermelon flesh into cubes or balls, removing the seeds and rind, and single-layering them on a baking sheet to pre-freeze. Line the pan with parchment paper to prevent sticking. Give it a few minutes on the tray, and then transfer to a sealed freezer bag or container, leaving some space at the top.
When thawed, frozen watermelon will never be as firm and crisp as its original, fresh-picked self, since the high water content inevitably creates a slushy consistency. But luckily, this texture is just what you need for naturally sweet, flavorful smoothies, slushies, and icy toppings. You can also freeze the slush in ice trays and use the cubes to flavor sparkling water or cocktails.
Read at Tasting Table
[
|
]