Properties of Olive Oil

What is an Oil?

Oils are Lipids, and lipids dissolve in organic solvents such as methylated spirits. Lipids are insoluble in water. There are chemical sub-classifications of lipids. The principle lipids in olive oil are triglycerides.

What are Triglycerides?

They are large complex molecules (98-99% of oil composition)

They are comprised of three fatty acid molecules linked to a stable carbon backbone.

The fatty acid linkage sites may break and this is when they become free fatty acids, and as such, the higher the FFA level, the greater the breakdown has occurred.

There are various fatty acids found in olive oil. The most common is monounsaturated oleic acid.

Minor components (trace elements up to 1-2%) are not triglycerides, but instead are antioxidants, which is unique to Olive Oil.

Classifications

Virgin oil is obtained solely by mechanical (non-chemical) means from olive fruit.

Virgin Oils from press are sub-classified into:

• Extra virgin (EVO) which must have a perfect taste and smell and a maximum free fatty acidity of 0.8%
• Virgin which must have a perfect taste and smell and a maximum free fatty acidity of 1.5%
• Non-virgin oils either chemically extracted and/or chemically mended  ( pure olive oil  is a blend of non-virgin and EVO; light olive oil  similarly)

Free Acidity

This is a result of triglyceride breakdown or degradation. Perfect EVO has some intrinsic free acidity in the order of 0.15  0.25%.

The breakdown is the result of contact of oil with enzymes found in olive fruit and in microbes (lipases)

Disruption of intact cells within the olives will liberate the lipases.

Damaged fruit, either on the tree or occurring between picking and pressing will increase the free acidity.

Free acidity also rises slowly upon oil storage: This occurs more rapidly in heavy sedimented oil or in oil subject to light and/or heat. Hence good oils are stored in dark containers and in the cool.

EVO Antioxidants

These are present in trace amounts by weight and unique to olive oil, and are particularly potent. Very little is required to protect the oil from deterioration and similarly little is required to be ingested to see beneficial effects in human consumption. The family of chemicals include hydroxytyrosol, tyrosol, oleuropein etc. There appears to be a synergistic beneficial effect afforded those who consume olive oil together with antioxidants found in vegetables (eg tomato derived antioxidants).

These are found lacking in poor quality oil, refined oil ( pure  and light  olive oils) and oils stored for excessive time or at excessive temperature.

The antioxidants protect olive oil from quickly turning rancid. This same feature also protects the body lipids  of the consumer in a similar way.

Research has shown that Olive Oil has been a significant contributor to benefits enjoyed over centuries to trad ional following of Mediterranean diets.

Vegetables have inherent antioxidants; so sprinkling extra virgin olive oil on your favourite vegetables increases the number and type of antioxidant intake, which further helps to protect our bodies.

Recently it has also been found that quality olive oil contains Depermein  which is a chemical found to be lacking in patients of Parkinsons Disease. This is still under research and no conclusions have yet been made.

Nutritional Facts

Not a significant source of dietary fibre, sugars, Vitamin A, Vitamin C, calcium and iron.
* Percent Daily Values are based on a 2,000 calorie diet.