When you grow olive trees, the question of why there are black olives and green olives seems quite incongruous. But it’s a question that has been on our minds for a long time, even before we started growing them. Obviously, an olive is black when it is fully ripe, and as long as it is not, it is green; but it can also be purple or turning between the two stages.
The choice of harvesting obviously depends on the destination of the olives. To simplify, one could say that green olives are destined for the confectionery industry, of which there is a large presence in the Marrakech region, and that black olives are crushed to make olive oil. However, in reality, olives can be processed for confectionery and olive oil regardless of their stage.
The confectionery prefers the green
The preferred destination for green olives is the confectionery industry, where producers begin harvesting them in September and whose selling price is often the highest of the season. These olives are hard and very bitter and can only be eaten after treatment.
In the villages, this treatment is done in a traditional way: the olives are soaked in water that is changed regularly during a month until they lose their bitterness. However, before putting them in the water, the women break or split them. Then, they are kept in water and taken out as needed.
However, soda is a more effective treatment. To remove the bitterness of the olives, the Romans used ash rich in soda and potash. Today, the industry does not bother with these constraints: the olives are soaked in soda for 48 hours.
For black olives, the treatment is different. Traditionally, they are rolled in salt and laid out in the sun or in a jar. This is a treatment that requires patience, since the olives must be returned to regularly until they have stabilized. Then, they can be stored in the cellar for two to three years.
The oil prefers the black olives
Olive growers prefer to crush black olives. The main reason is the yield: it is when an olive is at full maturity that the oil yield is the highest. In the region, the oil mills operate until early February. The yield is at its peak, and the oil that comes out of the presses is strong, appreciated by local consumers.
Yet, nothing prohibits crushing olives that are still maturing, or even green. If we lose in yield, which can be divided by two, we gain in fruitiness. This oil, fiery and astringent when it comes out of the press before softening after two months, exhales a very powerful smell of fruit, which is found in the oil.
It is a more precious oil, ideal for salads, and for those who like to dip their bread in it for breakfast, an old Mediterranean tradition.
