Olive Oil - Frequently Asked Questions

What is Extra Virgin olive oil?
The highest grade of olive oil available. It must have a acidity level less than 0.8% measured as free fatty acid, declared as oleic acid; and a peroxide value of less than 18 meq/kg, to comply with the International standard set by the International Olive Oil Council. This is tested and certified by an independent laboratory. No additives can be added to classify the oil as Extra Virgin Olive Oil.

What are the other grades of olive oil?
There are internationally two clearly defined grades of olive oil, 'Virgin' and 'Refined'.

In the virgin olive oil range the grades are Extra Virgin, Virgin, Ordinary and Lampante (lamp). These genuine unadulterated olive oils are graded by their free fatty acid content with extra virgin less than 0.8%, virgin being less than 2% and lampante more than 3.3%. Lampante (lamp) oil is just that; or to be used in food chain, must be refined, as below.

The 'Refined' olive oils are frequently found in the food chain. These oils are usually from the second pressing or subsequent; and are often heated above 35 deg to extract more oil and thus are not considered cold pressed or virgin. They are then processed through various filtering systems. There is plenty of mislabeling to mislead the consumer as to what grade the actual oil is.
The grades are Refined, 'Pure' olive oil, Crude Pomace oil, Refined Pomace oil, and Olive-pomace oil.
There has been some impetus to classify pomace oil as a non food chain commodity in Europe, which has no conclusion to date.

Does colour determine the quality of the oil?
Colour is not is not an indicator of the oil quality and oil is not judged with any consideration to colour.

What is 'cold pressed'?
Cold pressed means that the oil is processed under 35° centigrade. More oil can be extracted at temperatures exceeding 35°, but it is of a lower grade and is usually refined to be used in the food industry.

What is the fat content of olive oil?
Olive oil has 485 kilojoules (115 calories) per tablespoon, the same as any other oil. It is cholesterol free. Monounsaturated fats such as olive oil lower the damaging LDL-cholesterol (low density lipoproteins) which are responsible for depositing cholesterol in the arteries, and leave the beneficial HDL-cholesterol (high density lipoproteins) untouched or even at a higher level. Olive oil has antioxidants in great variety. These are needed to prevent the harmful LDL-cholesterol from becoming oxidised. Olive oil and olives are an essential part of the traditional Mediterranean diet which nutritionists are recommending as one of the most healthy diets. Click here for more about the Mediterranean diet and health benefits of olive oil.

"Total Cholesterol is fairly meaningless as a single indicator of hardening of the arteries, it is the 'good' (HDL) and bad (LDL) which matter. I see many people with heart attacks who have total cholesterol less than the recommended 5.0 , but their bad LDL may be 3.2 -the LDL is what counts and which needs to be LESS THAN 1.7 in a person with known heart disease or under 2 in all diabetics (adults). Olive oil ( as well as grape seed oil and the like) and also the Omega 3 and 6 'fish oil' compounds change how the body metabolizes and makes the triglycerides and which portion is HDL or LDL. These plant oils lower LDL.

The medications which are sometimes so vilified (the statins- lipex-simvastatin) lower LDL but actually reduce heart attack and stroke much more by a whole different biological mechanism- they reduce inflammation and oxidative stress of the cells. Olive oil and Fish oil also have the same- although not so strong, based on the dose as these powerful medicines .

My background on my fathers side is Italian. When I was growing up we ate all the time with his parents and other Italian relatives. There was always olive oil in deep dishes at every meal. I think they used a gallon every few weeks. The amount most Kiwis use is really just for the brief taste, and has not gotten to the daily amounts which change health." - Dr. Dan Tartaglia

Does Olive Oil get better with age?
Olive oil does not mature with age and is at its best soon after processing. The recommended period is 2 to 2 1/2 years from harvesting to consumption. Even the best oil will start to loose some of its characteristics after the first year from harvest.

Why is oil better stored in dark bottles and cans?
River Estate olive oil is bottled in dark glass to help preserve the excellent properties of the oil. Larger quantities are canned to eliminate the light as much as possible.

Olive oil in clear bottles start losing their qualities when exposure to light is prolonged, especially so, when exposed to fluorescent light for extended periods.

What else causes oil quality to deteriorate?
Heat and air are the other two elements that will cause your oil to deteriorate and exposure to both will shorten the life of your oil. The oil should be stored in a cool cupboard with the cap on to retain the high quality of the oil. Once opened, it is recommended that the oil be used within 3-6 months.

Can I use olive oil in my cooking?
Olive oil is excellent for stir frying, sautéing, deep frying, roasting and braising, and brushing on food before and during grilling and barbecuing. Olive oil can be heated to a much higher temperature in cooking that most other oils without damaging any of the fatty acids. It also forms a seal around food so that less fat is absorbed into the food. It can be filtered after frying and used up to 10 times, because olive oil is stable at high temperatures. Olive oil can also be used to make delicious moist cakes and bread.

How is Olive Oil Produced?

• The trees are picked by a combination of branch shaking and hand picking into a net under the tree.
• At the mill the olives are weighed, washed and the leaves removed.
• The olives then enter the crusher where they are broken down to a paste, which then drops into a mixing chamber.
• After a short time in the mixing chamber to allow the oil to come together after crushing, the paste is transferred into the second chamber.
• The paste is then transferred to a modern centrifuge system, which floats the oil off the paste, thus separating the olive oil.
• The oil is then settled in small vats before transferring to storage vats.
• The oil is bottled after approx 5-6 weeks of further settling.

^ Return to top of page ^