DID YOU NKOW So there is no black dye used but the olives are treated to make them a nice uniform dark black. Home curing of olives without these added salts will result in mottled and brownish olives which taste just as good but are not as attractive. The opposite tact is used to make a nice green California- style green-ripe olive.
Olives are harvested at a stage when they are green. They may be treated with dilute brine solution and lye (concentrated sodium hydroxide) to give the characteristic black colour. The olives contain phenolic compounds that undergo oxidation to quinones and subsequently form melanin, a dark black pigment. calcium carbonates and ferrous gluconate may be added to impart colour. The curing vat is aerated to provide necessary oxygen to accelerate colouring. No dye is used ` SOWCE1 GOT LOST IN THE INTERWEB
