Olive oil – described as “liquid gold” in Homer’s Iliad – is renowned for its health benefits. Not only is it delicious, it is anti-inflammatory, good for the gut, beneficial for the heart, and may even help us feel happier and live longer.

Scientists are now turning their attention, however, to the murky, brown and previously discarded by-product of its production – olive mill wastewater (OMW) – and have discovered it may be an even more powerful superfood.

OMW is left over after olives have been ground and their oil separated – a watery residue squeezed out from the remaining mulch.

It was previously considered a bit of a nuisance as, if not properly managed, it can contaminate surrounding soil and water, but now it is being commended for its protective and anti-inflammatory potential.