Aronia, or black chokeberry (Aronia melanocarpa), is a small, glossy blue-black pome-berry of a hardy North American shrub, famous for a flavour so mouth-drying and astringent it makes you "choke" — a fierce, dark, wine-like sourness backed by tannin and one of the highest antioxidant loads of any temperate fruit. Almost never eaten raw by the handful, it is a modern juice, extract and "superfood" crop.