Olives in their natural state are exceedingly bitter. I made that discovery by the roadside between Granada and Madrid when I reached up and plucked an olive from a tree. I later learned that olives are made edible by leaching out a bitter phenolic compound called oleuropein. This is done by pickling or curing techniques that were discovered some 7,000 years ago in Syria and Lebanon and basically consist of soaking the olives in brine, lye solution, plain water, or packing them in dry salt.
Brine curing is done in a saltwater solution for several weeks or months and allows the salt to draw out the oleuropein by osmosis. It also promotes a natural fermentation process by which the lactic acid bacteria present on the olives impart an additional tangy flavor. Using different salt concentrations and brining durations will result in a wide spectrum of tastes and textures, as will adding vinegar, herbs, and spices.
Another ancient method is dry salt curing, in which the olives are packed in layers of dry salt to draw out the moisture, also by osmosis. It causes the olives to shrivel and develop an intense, concentrated flavor. Once cured, they can be rinsed to remove the excess salt and then preserve them in olive oil to soften them and add a rich flavor. Dry-cured olives have a distinctive wrinkled appearance and a robust, slightly chewy texture.
A less common approach, suitable for home preparation, is lye curing. This rapid and efficient method is used in commercial olive production, particularly for green olives. It involves soaking the olives in a diluted lye (sodium hydroxide) solution, which quickly breaks down the oleuropein. The olives are then thoroughly rinsed with water to remove all traces of lye before placing them in a brine solution for their preservation and flavor development. Yet another technique, water curing, is a gentler method often used for green olives; it consists of repeatedly soaking the olives in fresh water, changing the water daily for a week or more often to gradually leach out the bitter compounds but leave just enough to give a fresh, sometimes slightly nutty flavor.
Olives have long been a staple of the Mediterranean diet. Mythology credits the goddess Athena with gifting the olive tree, Olea europaea, to the city that would bear her name, Athens. In the Abrahamic religions, the olive tree and its oil are frequently mentioned. The dove returning to Noah’s ark with an olive branch signaled the end of the great flood, solidifying its association with peace and renewal. Olive oil has been used to anoint kings and priests, symbolizing divine favor and consecration. In the New Testament, the Mount of Olives holds profound significance as a place of prayer and reflection for Jesus.
From the Middle East, the use of olive oil spread westward by migrating peoples on trade routes and to new civilizations. The olive became deeply ingrained in Greek culture to fuel lamps and also to anoint athletes. The Romans expanded its use and developed sophisticated methods of cultivation and pressing in the vast olive groves of their sprawling empire, from Spain to North Africa, providing a vital source of fuel, medicine, and food. The olive tree became a symbol of Roman prosperity and agricultural prowess, and its image often appeared on coins and in mosaics. In the Middle Ages, olive cultivation continued to thrive, often sustained by monastic orders who preserved agricultural knowledge and techniques. The olive remained a crucial commodity, especially when other sources of fat were scarce, to fuel lamps, lubricate machinery, and enrich culinary traditions. From Europe, Spanish and Portuguese colonizers introduced the olive tree to the Americas, where it found fertile ground in regions with Mediterranean climates such as California, Chile, and Argentina.
The nutritional value of olives is uncontested. Their health and medicinal value are less proven. Olives are rich in monounsaturated fats, oleic acid, vitamin E, polyphenols, flavonoids, and anti-inflammatory antioxidants. They raise the good cholesterol and lower the bad, seem to reduce blood pressure, are believed to reduce arterial plaque buildup, and lower the risk of heart attacks and strokes. They may even lower the risk of breast and colon cancer, reduce inflammation, and exert antimicrobial activities. Olives have even been claimed to protect the brain.
Some people like them best when immersed in a high-quality martini, especially of the Spanish Queen, Manzanilla, and Castelvetrano variety. You may prefer to partake of olives elegantly stuffed with pimiento, blue cheese, garlic, almonds, or jalapeños. For after all, you will only o-live once.