Olive oil is a vegetable oil extracted by pressing from olives, the fruit of the olive tree. We’ve been doing that for a while, as the use of olive oil can be traced back to 4,000 BC.
Olives have been harvested and eaten for thousands of years – long before the beginning of written history. The first evidence of cultivated olive trees dates back to 4000 BC in the Middle East, where olive oil initially had multiple uses, such as skin care, oil for lamps, but also medical treatments. Most of them comes from Mediterranean countries such as Spain, Italy, Greece, Portugal, France, Tunisia, Turkey, Syria and Morocco.
During the Renaissance, Italy became the largest producer of olive oil in the world and is famous for the rich and tasty oils that adorned the tables of noblemen and royal families throughout Europe. It’s popularity as an important ingredient in everyday cooking continues to grow in almost every culture thanks to its proven health benefits and nutritional properties.
An olive tree produces 5 to 10 kilos of olives per year. That’s enough for 1 to 2 liters of oil. 90 percent of the olives are used for the production of oil.
The olives are pressed 24 hours after harvesting. Oil comes from both the flesh and the seeds of the olive. The flesh contains 30-50% oil, the seeds 5%. The olive oil mill produces oil of different qualities and with different purity. After pressing an olive paste is formed. By carefully kneading it, the oil separates. This oil then goes into the centrifuge to separate the water from the oil. The last step consists of filtering and bottling the oil.
The oil comes from the flesh and seeds of the olive. It contains a lot of unsaturated fat, which is good for your health. Furthermore, this oil has a high content of vitamin E.
Olive oil is available in different varieties. There is oil of first pressing (Vierge), which is the mechanical method, which means that only pressure is applied. Nothing has been heated and no other means have been used. A special form of this is extra virgin oil: the most expensive quality oil with the most pronounced taste.
Then there’s refined olive oil: oil obtained by refining virgin oil. During refining, impurities are removed from the oil by heating and cooling. Some of the flavor is also lost.
Normal or plain oil has a more neutral taste than the more expensive qualities.
The ordinary oil and virgin oil are very suitable for baking and roasting. Frying in extra virgin oil is not recommended because this type of oil is less resistant to heat. It also loses most of its flavor after heating. Extra virgin oil is used cold for pasta, salad, vinaigrettes, tapenades and cold sauces. Extra virgin oil is less suitable for deep-frying. At this temperature harmful substances, such as PAHs, can form. The more often or longer extra virgin oil is heated, the more PAHs are formed.
The ordinary oil is purer and therefore more suitable for frying. Because this oil consists for the most part of refined oil, it does not change in quality and taste when heated. This oil can withstand heating better than hard fats.
Challenges in the production of olive oil are erosion, exhaustion of water sources and excessive use of pesticides – who all have their effect on prices. In general, this oil prices are affected by supply and demand. If less oil is produced, prices go up (assuming that global demand remains the same). This is why the harvest levels are so important– if olive crops are damaged and oil production drops, the prices go up.