Polyphenols in extra virgin olive oil

Polyphenols in extra virgin olive oil

 

Polyphenols are naturally occurring bioactive compounds that serve as the primary source of extra virgin olive oil's (EVOO) unique flavor and extensive health benefits. While olive oil is 98% fat, the remaining 2% contains over 30 different phenolic compounds that protect the oil from oxidation and provide therapeutic effects to the consumer. 

We will talk about the health effects and the factors affecting polyphenol levels in extra virgin olive oil

Key Biological Relationships

The relationship between olive oil and polyphenols is defined by several critical functions:


  • Antioxidant Defense: Polyphenols neutralize free radicals, protecting cellular DNA and membranes from oxidative stress linked to aging and chronic diseases.

  • Anti-Inflammatory Action: Compounds like oleocanthal work similarly to ibuprofen by inhibiting pro-inflammatory enzymes (COX-1 and COX-2).

  • Cardiovascular Protection: They improve lipid profiles, protect LDL cholesterol from oxidation, and enhance the function of "good" HDL cholesterol.

  • Gut Health Interaction: About 90–95% of ingested polyphenols reach the colon, where they act as prebiotics, feeding beneficial bacteria (e.g., Lactobacillus) while suppressing harmful pathogens. 

Primary Phenolic Compounds


  • Hydroxytyrosol: One of the most potent natural antioxidants; it is highly bioavailable and primarily protects blood lipids.

  • Oleuropein: Responsible for the bitter taste; it exhibits strong antimicrobial, antiviral, and cardioprotective properties.

  • Oleocanthal: Causes the peppery "sting" in the throat; noted for its neuroprotective effects and Ibuprofen-like anti-inflammatory activity. 

Factors Affecting Polyphenol Levels

Polyphenol concentration varies significantly (from 50 mg/kg to over 2,000 mg/kg) based on several factors: 

  • Processing: Extra Virgin Olive Oil (EVOO) contains the highest levels because it is not refined. Refining processes (heat/chemicals) strip away nearly all polyphenols. No chemicals added when obtaining the juice of the olive

  • Harvest Timing: Early-harvest olives (green) have much higher phenolic counts than late-harvest (ripe/black) olives. Early harvest falss into September and October, envero moment ( green,purple and black olives)  is October-November and ripe is end of November and December

  • Olive Variety: Certain cultivars like  Picual and Cornicabra from Spain, Coratina from Italy and Koroneiki from Greece are naturally richer in polyphenols.

  • Storage: Exposure to light, heat, and oxygen can degrade polyphenol content by up to 40% within weeks. 

The European Food Safety Authority (EFSA) permits a health claim for olive oils containing at least 5 mg of hydroxytyrosol and its derivatives per 20 g of oil. These oils are officially classified as "high polyphenol" (typically ≥250 mg/kg) and are proven to protect blood lipids from oxidative stress. 

Most commercial extra virgin olive oils have 100-250 mg/kg of polyphenols. Some have even more than 300 mg/kg. The European Food Safety Authority says olive oil should have at least 5 mg of hydroxytyrosol and its derivatives per 20 g to be eligible to carry the EFSA health claim.

At home, you can test olive oil by tasting its bitterness and pungency. These flavors mean it has more polyphenols. For more exact numbers, you need a lab test.

A Note on Cooking

 

High temperatures can degrade polyphenols, so it’s best to avoid cooking with high-phenolic olive oil. Use it as a finishing touch instead.


  • Use Raw: Drizzle olive oil over salads, soups, or steamed vegetables.

  • Add to Smoothies: A teaspoon blends seamlessly into green or berry smoothies.

  • Pair with Polyphenol-Rich Foods: Combine olive oil with other superfoods like tomatoes or leafy greens for a higher effect.

 

Back to News