More and more people are eating olives and we also use more and more olive oil in the kitchen. The fruit has a reputation for being very healthy. But is that true? And is there a difference between green and black olives?
Are olives healthy?
Olives contain about 12 g of fat per 100 grams but about 82% of which is an unsaturated fatty acid. These fats are associated with a reduced risk of cardiovascular disease. They are also known to reduce total cholesterol and LDL (bad cholesterol) levels in the blood. That is actually the most important asset of olives and olive oil for our health: they are an important player in the fight against cardiovascular diseases (source).
Olives also contain phenolic compounds that have beneficial properties, but not much is known about their profile as ‘antioxidants’. Their antioxidant content is also influenced by the ripeness of the fruits, the variety, and the way they are pickled or preserved.
Keep in mind that olive oil, like other types of oil, is also high in calories and canned olives contain a lot of salt. For this reason, they should be consumed in moderation.
What is the difference between green and black olives?
Real black olives are actually fruits because they grow on a tree: the olive tree or Olea europaea. There are many species and there are different ways to catalog them. But in order not to make it too complicated, we stick to the most common classification, namely that of green olives and black olives. These are not two different varieties or varieties, they grow on the same tree!
- Green olives are the unripe fruits that are picked at an early stage of their developmental stage. They are slightly fruitier in taste.
- Black olives have been given time to ripen on the tree. They have developed a fuller taste but are sometimes less juicy and softer in texture. They look a bit wrinkled and are very intense brown, black or purple.
However, don’t be fooled: the smooth black olives that are on the shelves of your local supermarket are usually green ones that have been processed with caustic soda (for oxidation) and a stabilizer such as iron gluconate (for color preservation) that gives them a black color. The bitter taste, typical of quality olive, is often masked in this treatment method and canning. Another way to check that it is not about artificially colored olives is the presence of the seed. Ripe black olives are too soft to deseed.
Olives are only suitable for consumption after they have spent six months to a year in a brine bath. Freshly picked olives are very bitter and really not to be eaten.
Some well-known quality varieties are Arbequina olives from Spain, Kalamata olives from Greece, the French olives de Nyons, the Bella di Carignola and Taggiasche from Italy. Olives that are marinated or preserved with the kernel are usually juicier and also have a longer shelf life.
How is olive oil made?
Olive oil is pressed from the flesh (with the kernels) of ripe olives. It is usually harvested from November to January, depending on the type of olive. The fruits are picked by hand or, especially for younger plantings, mechanically shaken from the tree.
As soon as possible after harvesting, the fruits are washed and ground into a paste. After that, a first cold pressing takes place (in which the temperature must not exceed 28 °C). Immediately afterward, the oil-and-water mixture that is released is separated via a centrifuge.
Nowadays, few olive oils are cold-pressed and centrifugation is done immediately. The advantage of this method is that the kernel remains intact, which also benefits the taste (less bitter).
With the powerful appliances that the olive farmers currently have at their disposal, all of the oil is extracted from pasta from the first processing, so there is actually no need for a second pressing.
Extra virgin vs virgin olive oil?
What exactly is the difference between virgin and extra virgin? The International Olive Council provides clear guidelines on this.
- Extra virgin olive oil is an oil obtained from the first cold pressing, which must be done mechanically and without chemical additives. It may contain a maximum of 0,8 % free acids.
- In the case of virgin olive oil, the acidity may not exceed 2%.
Still, you better watch out. Nowadays, these names no longer guarantee 100% quality.
Real quality extra virgin olive oil can be recognized by the smell, the color, the packaging, and of course also by the taste. It is very aromatic, intensely green or yellow colored, always packed in a dark bottle that protects it from light, and it tastes fruity. You can also immediately tell the difference in the price. And that makes sense when you consider that 1 liter of real extra virgin olive oil is made typically with 5 to even 10 kg of olives. Real extra virgin olive oil is mainly used in dressings and to finish pasta or pizza.
Ordinary olive oil is a mixture of virginity with refined oil. It is much cheaper and also has a more neutral taste. Refined oil is obtained by heating the first pressing to remove the impurities. That process also has an impact on the taste. Such a cheaper type of olive oil, the traditional olive oil, is ideal for baking but usually does not tolerate high temperatures (e.g. stir-frying). Avoid letting (olive) oil get too hot that it smokes because that is really not healthy.
Store olive oil in a fresh place (cellar or cool storage room) away from sunlight and always close the bottle tightly.