Olive Olea europaea

The olive tree, famed for its bitter fruit and healthy oil, has a well-documented history going back thousands of years. From Noah and the dove with the olive branch to Roman poet Horace's diet, olives have played an important part in our culture.

The olive tree is one of the most referenced plants in written history, appearing in the works of the Roman poet Horace, Homer's Odyssey, as well as numerous mentions in the Bible and the Qur'an. Its fruit and oil is one reason for its fame but it also has great symbolic significance.

In ancient Greece, winners at the In ancient Greece, winners at the Olympic Games were given olive wreathes to indicate victory and honour, while in the Bible a dove brought Noah an olive branch that signalled the end of the great flood. In many western cultures, we still use the phrase 'extending the olive branch' to represent a gesture of peace.

Today, the oil of the olive tree is probably best known for its use in cooking. To extract the oil, the olives are ground into a paste and then placed in a press which separates the oil from the paste. More than 750 million olive trees are cultivated for oil, the vast majority of which are in the Mediterranean region. In terms of quantity produced, Spain accounts for the most, followed by Italy and then Greece. It is also used in cosmetics, medicines and as a fuel.

The fruits of the olive tree are naturally bitter and are usually soaked in a solution of caustic soda and washed to remove oleuropein, a bitter carbohydrate. Green olives are fermented and then stored in brine. Black olives tend not to be fermented, and as a result taste milder than their green counterparts.