What are the polyphenols in olive oil?
Polyphenols are a group of chemical compounds in most of vegetables. For example, there are polyphenols in tea (flavonoids), beer, red wine (tannins), chocolate, and in olive oils (tirosoles).
Properties of polyphenols.
In general, polyphenols have antioxidant and anti-inflammatory properties. In olive oils, polyphenols protect the fatty acids of the olive oil from oxidation, which prevent the rusting fat in the bloodstream avoiding the formation of atheromas plaques in the blood vessels. There are also indications of the antitumoral properties of polyphenols.
Features of the polyphenols in olive oils
The amount of polyphenols can vary significantly between different olive oils. Their levels in olives are maximum just before the veraison, i.e. in green olives or at the moment that they change from green to purple. Therefore, the early harvested green olive oils will have more amount of polyphenols than others.
Another subject of that depends on the amount of polyphenols is the variety of olive trees. There are some in which levels of polyphenols are higher than in others. For instance, olives from the picual variety tend to produce more polyphenols than arbequina.
How is it possible for a consumer to know if the olive oil has abundant levels of polyphenols?
There are several clues that the consumer can check to know it:
First, the olive oil has to be Virgin because the refining process removes most of the polyphenols in the olive oil.
Second, it is important that the virgin olive oil is of early harvest. An indication could be the color of the olive oil. In general, the more green, the better. Late harvested olive oils tend to be more Golden.
Third, the virgin olive oil must have a certain bitter taste, leaving a slight pungency in the throat. Polyphenols add to the olive oils that bitter flavor due to the oleuropein, an exclusive polyphenol of olive oil. On the other hand, the pungency in the throat is due to the oleocanthal, another different polyphenol of the olive oil, which has strong anti-inflamatory effects, and that is a natural "version" of ibuprofen.
Fourth, it is important to know the year of harvest. The olive oil should be from the last harvest because the polyphenols are oxidized and loose their properties quickly. So, it is a good idea check in the label the year of harvest (although only the top quality extra virgin olive oils tend to indicate it).
Fifth, and this is the easiest clue, if it is written on the label. The problem is that the issue of the polyphenols in olive oil has not been developed yet, there are different procedures for analysis that are not equivalent, and most of producers neither do any analysis nor are focused to get extra virgin olive oils with high levels of polyphenols.
However, the International Olive Oil Council (IOOC) has already approved an official method of analysis of polyphenols and the EU, in its list of authoritative statements from properties of the healthy food, has included the polyphenols of olive oils as a beneficial substance.
The sentence that EU allows to be written in the labels of olive oils with high levels of polyphenols is:
"The polyphenols of the olive oil contribute to the protection of the blood lipids against oxidative damage”.
This statement may only be used on the labels of olive oils with a concentration of polyphenols over 5 mg per 20 g of olive oil. (250 mg/kg)
In order to have an idea about it, 20 gr is more or less a tablespoon and a half of olive oil. In the list of EU (EU Regulation no. 432/2012 of the Commission) is also indicated that these 20 gr is the minimum daily intake to get the beneficial effects from polyphenols.
Polyphenols in Las Valdesas Olive Oils:
We have been studying the concentrations of polyphenols in our olive oils for a long time. We have got values of 500 mg/kg in some of our varieties and in all of them we have exceeded the levels of 250 mg/kg. However those analysis reports were done just after milling the olives, and we still don't have details for the levels of polyphenols in an entire year, so that we cannot guarantee that these levels have been maintained throughout the year on the minimum required by the EU.
Henceforth, our intention is to publish the results of our olive oils at the beginning of campaign for knowledge of our customers and consumers. To find out the amount of polyphenols, you can check the reports of the olive oils of the last harvest.
You can learn more benefits of Extra Virgin Olive Oil here.