Dragon fruit

Look for bright, evenly coloured skin and give it a gentle press: it should yield slightly, like a ripe kiwi, without feeling mushy. Dry, brownish tips on the scales are normal; avoid fruit with large soft patches or split skin.

Slice it in half lengthways and scoop out the flesh with a spoon, or peel away the skin and cut the flesh into cubes. The tiny black seeds are edible, so there’s no need to remove them.

Keep an uncut fruit at room temperature until it yields slightly to gentle pressure, then refrigerate it if you want to slow ripening. Cover cut flesh and refrigerate it; use it within a couple of days, as it softens quickly.

Its mild, refreshing flavour works with lime, mint, berries and mango. Add cubes to a fruit salad or yoghurt, or blend them into a smoothie with banana and a squeeze of lime.

Yes. Peel it, cut the flesh into cubes and freeze the pieces in a single layer on a tray; once firm, transfer them to a sealed container. Blend the frozen cubes straight into smoothies.

Prickly pear has more, with 4.6 g per 100 g compared with 2.4 g in dragon fruit. Both fruits have edible seeds.

The skin is not usually eaten: it is tough and can have an unpleasant texture. Peel it away or scoop out the flesh, and wash the fruit before cutting so the knife does not carry dirt from the outside to the flesh.