-3 lebanese cucumbers, unpeeled, cut into 3cm lengths, plus extra wedges, to serve
-55g (1/4 cup) caster sugar
-1L sparkling mineral water, chilled
-3 limes, juiced
-Ice cubes, to serve
DirectionsWorking in 2 batches, blend pineapple, cucumbers, sugar, 250ml (1 cup) sparkling water and a pinch of salt in a blender to a purée. Strain through a fine sieve into a bowl, stirring vigorously and pressing down with a spoon to extract as much juice as possible. Discard pulp. Blot top of juice mixture with paper towel to remove froth. Transfer to a jug, cover with plastic wrap, then refrigerate until needed or for up to 1 day.
When ready to serve, stir in lime juice. Half-fill glasses with ice, then fill three-quarters full with juice mixture. Top up with sparkling water. Place a cucumber wedge in each to serve.