The quality of olive oil that we consume depends on the source – the tree from which the olives are procured. Real olive oil comes from trees that are grown in a sunny, subtropical Mediterranean climate. The olive tree can live for more than 100 years. The best fruit-bearing years for an olive tree are from age seven to thirty-five.
The best olives grow in soil and climate that also nurture grapes. So, it is not uncommon to find that real olive oil can often be traced to olive groves in regions that also nurture some of the finest vineyards.
The harvesting techniques used influence the quality of the olive oil in terms of flavor and purity. If handled roughly, any fruit is liable to damage. And olives are no exception. Olives that are struck down using sticks or machines suffer damage to their skin and flesh. Sometimes, growers prefer to let the fruit remain on the trees till it falls down on its own. Such fruit, though obtained cheaply, does not offer uniform quality because some of the fruit may be overripe, while some may be raw. Consistent quality of the fruit is an important pre-condition for quality olive oil.
In order to guarantee the best quality olive oil with all its subtle flavors intact, the most meticulous olive orchard owners pick the fruit by hand. The process is labor-intensive and adds to the cost of production, but it ensures that the olive oil you consume is of the highest quality and actually carries the goodness that olive oil is meant to have.
An olive's color indicates its ripeness. Ripe fruit is generally a shade of black. Olives mature from green to red to black. Green olives are plucked in the months of September and October. September heralds the start of the harvest season. Green olives possess a characteristic nutty and astringent taste. By December, the olives are black with a softer skin and a meatier bite.
Olive oils get their very distinctive flavors from the fruits that yield oil. The soil, climate, cultivars, and harvesting and curing techniques determine the flavor and grade of olive oil.
Popular olive oil varieties include Arbequina, which comes from the northern parts of Spain. It is an aromatic olive oil and almost devoid of bitterness. This oil must be consumed quickly, it does not store well.
Ascolano olives are used primarily as table olives, mainly because the oil yield, though fragrant, is very poor.
Leccino is a popular Italian variety found in many high-end olive oil blends. The fruit yields a fair amount of oil that possess robust flavor.