By
Diego Cortés
Watermelon rind jam is one of the oldest preserves in zero-waste cooking: the white rind, the part that usually goes in the bin, simmers with sugar and lemon until it turns translucent, with the texture of a confiture and a flavour that runs from tender melon to candied citron. In Chile it is known as dulce de cáscara de sandía and it is compared to alcayota sweet, because both come out amber and dense.
It works because that part of the fruit is mostly water and fibre, but it also brings natural pectin: no shop-bought pectin is needed, only cooking time and a little acid. One kilo of rind yields 1.2 kg, roughly four 300 ml jars.
Spread it on toast, serve it with fresh cheese or use it to fill tarts. If you like home preserves, try the homemade lemon jam and the alcayota preserve; and if you have watermelon left over, the summer salad with watermelon uses it up without turning on the stove.
Prep
25 min
Cook
70 min
Servings
24
Calories
90 kcal
Cut the watermelon into wedges, scoop out the red flesh with a spoon and set it aside to eat: only the white rind goes into the jam.
Peel each wedge with a knife or peeler until every bit of hard green skin is gone; keep only the white part and, if you want colour, a paper-thin strip of red.
Weigh the cleaned rind: the sugar is calculated on that weight, at 500 g of sugar per kilo of rind.
Cut it into 1 to 1.5 cm cubes, all the same size, so they cook evenly instead of ending up half hard and half mushy.
Blanch them for 3 minutes in the 2 litres of boiling salted water, drain and rinse under cold water: this pulls out the bitterness of the skin and firms up the flesh.
Put the cubes in a pot with the sugar, the lemon juice and zest, the orange zest, the cinnamon, the cloves and the ginger, and let them macerate from 2 hours to overnight, until they release their juice and the sugar dissolves.
Cook over medium-low heat, uncovered, for 55 to 70 minutes, stirring every 10 minutes with a wooden spoon, until the liquid thickens and the cubes look translucent.
Test the set: drop a teaspoon onto a cold plate and tilt it; if the jam does not run, it is ready. If it is still liquid, cook 10 more minutes and test again.
Fish out the cinnamon and cloves, taste, and adjust with the extra teaspoon of lemon juice and the pinch of salt; for a smooth jam, blend it for 20 seconds with a stick blender.
Sterilise the jars by boiling them for 10 minutes, dry them upside down and fill them with the hot jam, leaving 1 cm of headspace.
Seal the jars, turn them upside down for 10 minutes to pull a vacuum and, if you want to store them outside the fridge, boil them in a water bath for 15 minutes.
This recipe has a easy difficulty level, which means it's accessible for cooks of all levels.
The preparation time is 25 minutes and the cooking time is 70 minutes.
This recipe is designed for 24 servings.
Yes, many ingredients can be substituted with similar alternatives. We recommend checking the recipe variations.
Store the preparation in the refrigerator for up to 3 days in an airtight container. Some preparations can be frozen for up to 3 months.
