Polyphenols & Olive Oil
Polyphenols are what give Olive Oil its distinct taste and long shelf life. A few Extra Virgin Olive Oils contain far more, (up to 500% more) than others. Polyphenol intake has been known to help out with lowering incidence of cancer and coronary heart disease (CHD).
A few key aspects to consider when seeking an Olive Oil with high levels of polyphenols:
- The time of harvest
- The variety
- The method of extraction
- And the management of the grove
...will affect the phenol count .
Did you know that processing or refining Olive Oil actually destroys Polyphenols? Refined Olive Oils similar to "pure olive oil," "lite/light olive oil," and "pomace olive oil" have little-or-no Polyphenols, but the same amount of calories as Olive Oils that do.
In addition, heat, light, oxygen, and time cause Polyphenol levels in Olive Oil to lessen.
Usually, more robust oils have higher phenolic compounds than the milder oils. A phenol count of less than 120 (as expressed by mg/kg) is thought of as low. Virgin oils with a phenol count between 120 and 220 are thought of as medium.
Olive Oils with a count above 220 are considered high in Polyphenols. Some of the more acute Extra Virgin Olive Oils will contain levels of 350 or higher.
Oleic Acid (Omega 9) & Olive Oil
Oleic acid is a monounsaturated omega-9 fatty acid. Monounsaturated fat is generally discovered at the ever changing concentrations in virgin Olive Oil, and it is known to aid with lowering the risk of heart attack, arteriosclerosis, and cancer.
Virgin Olive Oils containing higher levels of Oleic Acid typically tend to be more stable and hold up longer. In this sense, high Oleic Acid acts as a natural preservative. Additionally, Oleic Acid is regularly measured in Olive Oil by percentage. The levels normally range from 45% to 80%+.
Free Fatty Acids (FFA's) & Olive Oil
In a sense the FFA level is an indicator of the condition of the fruit at the time the oil was extracted-- it's like a freshness quotient. Ripeness acts as a pivotal role in the level of FFA's.
Overripe fruit generally produce a higher yield of oil to olive by weight, but the free fatty acids go up as well. Once the fruit has been chosen or the skin is broken, the fruit decomposes at a much faster pace. When Olive Oil is revealed to air, light, or heat, decomposition goes up until the oil starts to go rancid and becomes unfit for human consumption.
Peroxides & Olive Oil
Peroxides are naturally occurring compounds in all edible oils. Peroxide values go up over time. These are generally indicators of the level of oxidation at the time of processing, and they go up according to storage conditions.
Poor storage conditions will develop quick oxidation and rancidity. High peroxide levels are a sign of bad processing practices, substandard fruit conditions, old age, improper storage, or any combination of negative conditions. The IOOC rules state that Extra Virgin Olive Oils must display a peroxide value lower than 20.