Blue olives are a type of Ceylon olive (Elaeocarpus serratus) indigenous to Sri Lanka. It grows in the west and centre of the island in medium size trees with leaves similar to the avocado. Known locally as Nil Veralu (in Sinhala), this tropical fruit is found across the Indian Subcontinent, Indo-China and South East Asia.
While the green variety of veralu looks just like the common green olive (Olea europaea), the blue olive is almost perfectly spherical in shape with a bright blue edible skin.
What Does Blue Olive Taste Like?
The blue olive has a firm green flesh with a pasty, avocado-like texture. It is astringent when unripe, and slightly sour when ripe. In its native home in Sri Lanka, varieties of Ceylon olives are used in ways very different to how Mediterranean olives are typically used.
The sour, ripe olive is a popular ingredient found in the cuisine of Sri Lanka. Unlike the common olives that we are used to, that are often prepared in commercial environments pressed into oil or cured, the veralu olive is prepared in Sri Lankan homes and by street food vendors to create both savoury and sweet dishes.
Nil veralu, especially one referred to as young nil veralu by the locals, is used in pickles, boiled or eaten fresh, sprinkled in chilli and salt. In Sri Lanka, street side carts sell a pickle dish called veralu achcharu: Ceylon olives are first boiled, then squashed flat and served together with any combination of slices of guava, mango, veralu, green chillies, pearl onions, carrot, doused in a fiery thin dressing of vinegar, chilli powder, mustard seed and sugar.
The blue olive also has a significant religious meaning across various surrounding countries where many believe that nil veralu are equal to good blessings. In some Hindu and Buddhist cultures the seeds of varieties of nil veralu are used to make the beads in prayer necklaces.
Veralu fruit have also been used traditionally for medicinal purposes in Sri Lanka, thanks to its high nutritional content of vitamins, minerals and fibre and antioxidants.
Blue is a rare colour found in natural food. Many foods that are referred to as blue often display a purple or green tinge, which comes down to the nature of the colour pigment. The blue occurs from anthocyanin that is an unstable pigment readily affected by the pH, easily seen by how the blue water from a boiled purple cabbage will turn red when an acid element (lemon, vinegar) is added to it.