Olive and Olive Oil Glossary

Definitions of the terms that recur in writing about olives and olive oil. Kept short; links point to fuller treatments.

Olea europaea

The botanical name of the olive; an evergreen of the *Oleaceae* family.

Oleaster

The wild olive (*Olea europaea* var. *sylvestris*), ancestor of the cultivated tree; small-fruited with little flesh.

Drupe

A stone fruit. Botanically the olive is a drupe, in the same class as plum and cherry.

Alternate bearing

The olive's habit of following a heavy crop year with a light one; it makes reading a trend from a single year misleading.

Invaiatura / veraison

The ripening stage at which the fruit turns from green to purple and then black; for many growers the ideal harvest window.

Chill requirement

The period of winter cool the olive needs in order to flower; in climates without winter the tree lives but sets no fruit.

Sucker / water shoot

A vigorous, non-fruiting shoot from the base or trunk; it draws the tree's strength and is removed year-round.

Oleuropein

The polyphenol that gives raw olives their sharp bitterness; the tree's own defence, removable by curing because it is water-soluble.

Curing / brining

The whole process of removing an olive's bitterness in water, brine, dry salt or lye.

Dry-salt cured olives

Ripe black olives cured in layers of rock salt in perforated baskets; wrinkled and intensely flavoured.

Cracked olives

Olives scored or cracked so the bitterness leaches faster; quicker to cure but softer in texture.

Ferrous gluconate (E579)

The additive used to darken green olives chemically. Declaring it is mandatory; the ingredients list is the surest way to tell it from naturally ripened black olives.

Extra virgin

The grade extracted by mechanical means only, with free acidity at most 0.8% and no defect in the sensory panel.

Virgin

Also mechanically extracted, with acidity up to 2% and slight sensory defects tolerated.

Lampante

Virgin oil with sensory defects or high acidity, unfit for direct consumption; it goes to refining. The name recalls its old use as lamp fuel.

Refined

The grade produced by treating defective or high-acidity oil with heat and chemicals; acidity falls but most aroma, flavour and polyphenols are lost.

Olive oil (riviera)

Refined oil blended with a little virgin oil; usually labelled simply "olive oil".

Pomace

The pulp left after pressing — skin, stone and flesh residue — used as fuel, fodder and the raw material for pomace oil.

Pomace oil

Oil extracted from pomace with solvents. It is not olive oil in the strict sense; labelling it as pomace oil is mandatory.

Vegetation water

The heavily organic waste liquid released from the fruit during pressing; polluting to soil and water if left untreated.

Free fatty acid

The measure of breakdown in the oil, expressed as a percentage of oleic acid; this is what "acidity" means. It has nothing to do with sour taste.

Peroxide value

A measure of how far the oil has oxidised; read alongside acidity, which is not sufficient on its own.

K232 / K270

Ultraviolet absorbance measurements that reveal refining and oxidation products.

Sensory panel

The official method by which trained tasters assess an oil for defects and positive attributes; the extra virgin grade requires zero defects.

Fruity

The fresh aroma and taste from sound fruit; one of the positive attributes in tasting.

Bitterness

A positive attribute linked to polyphenols and green fruit — not a defect.

Pungency

The sharpness felt at the back of the throat on swallowing; linked to oleocanthal and a sign of freshness.

Oleocanthal

The polyphenol responsible for throat pungency; identified in 2005, it stimulates the same nerve endings as ibuprofen.

Hydroxytyrosol

The principal olive oil polyphenol; the health claim authorised by the European Food Safety Authority rests on it.

Polyphenol

The family of compounds giving oil its bitterness, pungency and resistance to oxidation; largely lost in refining.

Tocopherol

The chemical name for vitamin E, one of olive oil's natural antioxidants.

Oleic acid

The monounsaturated fatty acid making up roughly 70-80% of olive oil.

Cold pressing

Production in which the paste is not taken above 27 °C, limiting the loss of aroma and polyphenols.

Malaxation

The stage in which the crushed paste is slowly stirred so oil droplets coalesce; time and temperature directly affect quality.

Decanter

The centrifugal machine that separates oil from water and solids in a continuous system; it has replaced the classic press.

Filtration

Straining out suspended particles; unfiltered oil is cloudier and, because it settles sediment, can spoil sooner.

Geographical indication

The registration granted when a product's name is identified with its place of origin; in Turkey granted by TÜRKPATENT.

Designation of origin

The type of geographical indication requiring ALL stages of production to take place in the stated area.

Geographical indication (mahreç)

The more flexible type, requiring only that AT LEAST ONE stage of production takes place in the stated area.

IOC

The International Olive Council, which sets olive oil grade standards and publishes world production and consumption statistics.

Where to go next

• Grades and labels: extra virgin, virgin, riviera · acidity · how to tell good olive oil
• Production: cold pressing · the harvest · curing
• Compounds: oleocanthal and polyphenols · nutrition
• Registration: geographical indications