EVOO Education

What is Extra Virgin Olive Oil?

Olive Oil is essentially olive juice and simply put, Extra Virgin Olive Oil is the highest quality olive oil you can buy. It is the result of the first cold pressing of an olive. To be classed as Extra Virgin Olive Oil, it can have no flavour defects and must have a free fatty acid level less than 0.8%. There is no chemical or heat treatment to the olives and has to be have fruitiness to its taste and aroma. Of all the types of Olive Oils, Extra Virgin Olive Oil is known to have the highest amounts of antioxidant and Polyphenolic profiles.


The production of Extra Virgin Olive Oil is an age-old art, dating back to early in Human history. The process essentially involves the harvesting of olives off the trees and cleaned from excess leaves and any debris. The olives are then ground into a paste either by steel or stone and then are put into a malaxer where the oil droplets can join together into bigger ones. Traditionally the malaxed olives are then put into a press, but modern technology has now allowed for a cleaner process called a centrifuge, where the oil and paste are separated. The oil is then transferred into tanks to settle from any sediment and finally racked off and stored in sealed, light and air proofed containers ready for bottling for the consumer.

How does olive ripeness affect Extra Virgin Olive OIl?

When the olives are harvested will affect the final fruitiness, bitterness and spice of the EVOO. 

Green Fruit, which is still immature, gives more of the bitterness and grassy notes you may be familiar with in some oils. Green fruit is generally higher in polyphenols and other antioxidants which means a stronger oil with a longer shelf life. The downside to green fruit is you will get less of the fruity notes and also less oil yield. 

Fruit that is in the process described as veraison, is the ideal timing to pick your olives. Veraison refers to when the olive is a mixture of green and purple, the middle timing of ripening olives.  The fruit still has a high Polyphenol content but has now developed some of the fruitiness that is desirable in a good Extra Virgin Olive Oil. The fruit also has just about the most oil content it will be able to give during extraction. 

Black/Purple Fruit is when the olives are fully ripe. An EVOO made with fully ripe fruit will have very strong fruity notes and be sweeter. However, by this stage the Polyphenol and antioxidants have started to decline which means the resulting EVOO would have a lot shorter shelf life and very little bitterness and spice to it.

How are olives harvested?

Traditionally olives were harvested by hand. Luckily, time and technology have advanced to be able to speed up the process now. Some olives are now harvested by a “shaker” method where the tree is gripped by a machine and the olives and leaves are essentially shaken off the tree into a fanned our net and then taken for harvest. At Rio Vista Olives we keep it a bit more traditional and use a combination of a few methods. We first of all place large nets under the trees so that the olives can be collected on completion. Then the trees are either hand raked with a small rake, mechanically raked by a larger rake attached to a power source or with our large Olivari harvest machine. The machine essentially brushes the branches for olive removal, much like the hand rakes, just on a larger, faster scale. This method is a lot gentler on the tree promoting a healthier tree and better future growth. The olives are then collected from the nets and promptly taken to the on-site processor to be turned into Extra Virgin Olive Oil, all within 6 hours.

Can i cook with evoo?

Yes. There have been multiple scientific studies that show it is fine to cook with Extra Virgin Olive Oil, even at higher heats. In fact, one recent Australian Study found that when heated, EVOO produced the lowest quantity of harmful substances called polar compounds in comparison to a variety of other oils commonly used in cooking such as canola, coconut, peanut, rice bran and sunflower oils. In the study they actually heated the olive oil up to 240 degrees Celsius, which is generally higher than standard cooking temperatures used for stir-frying, deep frying and baking. It showed that not only is Extra Virgin Olive Oil safe to heat and cook with, it is also the better choice in comparison to many others. It produced less polar compounds and trans fats. 

So not only can you use it to drizzle and dip with, you can essentially use it in most of your kitchen cooking safely and to the benefit of your family.

How should i store EVOO?

Without proper storage the Polyphenols and Antioxidants in EVOO can reduce by up to 50% in the first 6 months, so correct storage is very important. The enemies of Extra Virgin Olive Oil are heat, light, air and temperature. Like a good wine, you don’t want to destroy your EVOO with oxidation. Always store you EVOO in a dark, cool, glass container, and keep it sealed when not in use. Time is not your friend with EVOO. Fresh is best. Always try and buy an oil with the latest harvest date possible. The older the oil the less antioxidants and goodness it will contain, plus it will lose its freshness and vibrancy.

What should i look for in a good extra virgin olive oil?

All Extra Virgin Olive Oil comes down to personal taste and the application you are using it for. Some key things to remember when choosing an oil however, are: 

Colour gives no indicator of quality. You can have a vibrantly green oil and it can be full of defects or have no flavour at all.

Smell any oil before you taste it. A Good EVOO should have a clean, fresh nose to it, with no hint of mustiness or staleness.

Taste the oil and confirm that it has fruitness (or flavour) to it. A high quality Extra Virgin Olive Oil should have three important elements to it. Fruitiness, Bitterness and Spiciness. It should have a long palate to it and leave the mouth feeling fresh and clean, no heavy fattiness left in the mouth. 

EVOO blends of oil generally fit into 3 categories of flavour. Mild, Medium and Robust.  

A Mild EVOO is generally more delicate in the mouth and may not have much pungency. 

A Medium Oil, is generally a bit stronger in the pungency and have a bit of spice to it.

A Robust EVOO, normally has a party in your mouth. You'll have big notes of pungency and spice.

What's the difference between a single variety evoo and other extra virgin olive oils in your range?

Single Variety EVOO means that the oil is simply a single type of olive used. So the various names Kalamata, Koroneiki, Manzanillo etc. are all various varieties of Olives. Much like grapes come as Shiraz, Chardonnay and the like. When you are buying a single variety EVOO you have an oil that is 100% that particular olive variety. Each variety has its own flavour profile and antioxidant level and so you may find that there is a particular style or variety of olive you have a preference for. Much the same as a consumer having a preference to Shiraz over Cabernet Sauvingnon when it comes to a Red Wine.

When it comes to a blend of EVOO (still 100% Extra Virgin Olive Oil, not to be confused with blended oil that can be made up of inferior oils), this means that we have expertly blended various varieties of olives together post extraction to achieve a certain flavour profile in the oil. You may have 3 or 4 different varieties in a blend, giving it a different profile of fruitiness, depth, palate length and bitterness than what could simply be achieved with a single variety. Think of it as more the "Bordeaux" or "GSM" you would see in the Wine world, but for an EVOO.

As with all our Extra Virgin Olive Oil though, Rio Vista Olives only makes 100% South Australian Extra Virgin Olive Oil. No other oils are allowed into our bottles.