Amurca

Amurca is the Latin name for the bitter-tasting, dark-colored, watery sediment that settles out of unfiltered olive oil over time. It has been known in English as "olive oil lees"^[1] and recently as "olive mill waste water (OMWW)".^[2] Historically, amurca was used for numerous purposes, as first described by Cato the Elder in De Agri Cultura, and later by Pliny the Elder.^[3] Cato the Elder mentions its uses as a building material, pesticide, herbicide, dietary supplement for oxen and trees, food preservative, a maintenance product for leather, bronze vessel, and vases, and as a treatment for firewood in order to avoid smoke.^[4]

Amurca pit at one oil mill, in the province of Jaén.