The science of Premium Extra Virgin Olive Oil

Premium extra virgin olive oil (EVOO) is food of the gods… a timeless romance.

But to choose a good one we have to abandon the summers in the groves, the magical taste of a warm, soft bread dipped in a beautiful, fresh extra virgin olive oil .... and look at the science: the information about its chemical composition and exceptional sensory characteristics.

Let's take a look at several critical parameters: polyphenols, acidity (Free Fatty Acids or FFA), peroxide values (PV), and specific UV absorption values (K270, K232, Delta K).

Polyphenols

Polyphenols are a group of naturally occurring antioxidants found in top qulaity olive oils. These compounds contribute to the oil's stability, health benefits, and sensory properties (bitterness and pungency).

The major polyphenols in EVOO include oleocanthal, oleuropein, hydroxytyrosol, and tyrosol. They help protect the oil from oxidation, thus extending its shelf life and preserving its flavor and nutritional qualities.

Topline Health Benefits
- Anti-inflammatory properties
- Antioxidant effects
- Cardiovascular health improvement
- Potential anti-cancer properties

Optimuml Levels
- Premium EVOO typically contains polyphenol levels above 300 mg/kg.

Acidity (Free Fatty Acids - FFA)

Free Fatty Acids (FFA) measure the degree of hydrolysis of triglycerides into free fatty acids and glycerol. This parameter is crucial as it indicates the quality and freshness of the olive oil.

Measurement:
- Expressed as a percentage of oleic acid.
- The lower the FFA, the better the quality.

Standards:
- Premium EVOO must have an FFA level of less than 0.8%.
- High-quality EVOO often has FFA levels below 0.3%.

Factors Affecting FFA:
- Fruit quality
- Harvesting methods
- Storage conditions

Peroxide Values (PV)

Peroxide values measure the extent of primary oxidation in the oil, indicating the initial stages of rancidity. It is an essential parameter for determining the oil's freshness and oxidative stability.

Measurement:
- Expressed in milliequivalents of oxygen per kilogram of oil (meq O2/kg).

Standards:
- Premium EVOO must have a PV of less than 20 meq O2/kg.
- High-quality EVOO typically has a PV below 10 meq O2/kg.

Factors Affecting PV:
- Exposure to light, heat, and air
- Storage conditions
- Polyphenol content

UV Absorption Values (K270, K232, Delta K)

The UV absorption values (K270, K232, and Delta K) are indicators of the oil's purity and oxidative state. These values help detect the presence of oxidation products and potential adulteration with refined oils.

K270 Value:
- Measures the conjugated trienes and secondary oxidation products.
- Standards: Premium EVOO must have a K270 value of less than 0.22.

K232 Value:
- Measures the conjugated dienes and primary oxidation products.
- Standards: Premium EVOO must have a K232 value of less than 2.50.

Delta K Value:
- Assesses the difference between actual and baseline absorbance, indicating oil adulteration.
- Standards: Delta K should be less than 0.01 for premium EVOO.

Factors Affecting UV Values:
- Oxidative degradation
- Adulteration with lower-quality oils
- Storage conditions

So the quality of premium extra virgin olive oil is determined by a combination of its chemical composition and sensory properties. The technical info discussed above is a key guide to an oil's quality, freshness, and health benefits.

It's all about choosing the best EVOO, with superior taste, aroma, and nutritional value.