Green olives are olives picked while still unripe, before their color changes from green to black, giving them a firmer texture and a brighter, more acidic, less sweet flavor than fully ripened olives. Like all olives, they are naturally bitter straight off the tree and are cured, usually in brine, before eating.
Olive trees (Olea europaea) have been cultivated across the Mediterranean basin for millennia, and green olives are a staple in Greek, Italian, Spanish, and North African cooking; Spain is among the world's largest producers.
They turn up in salads, tapas, sauces, and dips; season tagines and couscous in North African cuisine; flavor pasta sauces and pizza in Italy; and are brined and served as a Greek appetizer. Their tangy, herbaceous flavor pairs well with citrus, garlic, anchovies, rosemary, thyme, oregano, tomatoes, and feta.