Buying Extra Virgin Olive Oil

Argh! Which extra virgin olive oil do I buy?!

That own-brand one, one in a big tin, one that seems vaguely artisan… and why 30 bucks for one when others are twice or three times the price? 

Confusing!

Here's a simple rule of thumb: if it's not certified, it could be (and most likely is) any old oil.

Our extra virgin olive oils have been lab tested.

(We sometimes add the certification documents to our product pages, though they get very technical and are often in other languages, but are alway available on request).

Lab testing provides vital data points that determine the quality of the extra virgin olive oil. These are some key ones:

Acidity - also called 'free fatty acids'. Your EVOO should have an acidity of less that 0.8. Any higher indicates too much oxidisation, which impacts healthy compounds and taste.

Polyphenols - measured in mg/kg. The range of mega-healthy compounds in EVOO that have literal superpowers, e.g. oleocanthal, oleuropein and many more.

Provenance - who made the EVOO and where; super important.

Harvest date or bottling date - (note: most premium EVOOs are kept under inert gas in optimum conditions, then bottled to order so harvest date can play a lesser role). The date needs to be within the last 18 to 24 months ideally.

After than there's lots more: peroxides, K values etc, which we discuss in in more depth here.

When you look at the label on a bottle of typical supermarket extra virgin olive oil, you're unlikely to get the information above, because the oil has come through a bulk commodity (unchilled) supply chain.

Sadly, these inferior oils don't provide the benefits of top quality extra virgin olive oil, and may even be diluted with cheap nut oils.

As for the Nutritional Information Panel (NIP), it's totally useless when it comes to determining the quality of what's in that bottle. (As well, the nutritional profile of all olive oils at a macro level is pretty much the same thing, ~73% monounsaturated fat.(Here's more detail on the NIP if you wanna go down that rabbit hole!)

At Olivver, you'll see a detailed profile of the EVOO we stock, with data like acidity, so you know it's the good stuff!

But hold the phones, there is one more way to find out how good an EVOO is.

Taste!

Try comparing a cheaper supermarket EVOO with a single estate or highly reputable premium extra virgin olive oil.

We guarantee once you have tasted the difference you'll be super unkeen to go back to the low quality stuff, which will just taste dull and fatty by comparison.

Even if it is labelled as 'extra virgin olive oil' & 'cold pressed'!

Expanding on those essential attributes:

• the acidity level or free fatty acids (FFA) - is a measure of oxidation in the oil. This needs to be less than 0.8%. The lower the better. A super premium EVOO could have an FFA reading as low as 0.1%. (No oil can ever be produced completely oxidation-free since we live in an oxygen-rich atmosphere, but it can be minimised).

• Polyphenols - the health rockstars in high quality extra virgin olive oil. Oleocanthal, , oleacein are a type of compound called 'secoiridoids', and unique to olives. Then there are the phenolic compounds like hydroxytyrosol and tyrosol… and lots more beneficial compounds including lignans, flavonoids and phenolic acids.

Polyphenol content in EVOOs typically ranges between 50 and 2000+ mg/kg in EVOOs, and they are credited with many of the health benefits linked with EVOO such as antioxidant properties and cardiovascular health support.

The trade off is that EVOOs with higher polyphenol concentration also tend to have a more intense, bitter flavour. An EVOO with 1500+ mg/kg may only be more useful - and tolerable - medicinally. 

The polyphenols in your premium extra virgin olive oil will very slowly decrease in concentration over time, so use the oil, don't let it suffer in the back of a cupboard.

As a rule of thumb, the more details on the label, the better. They signal a desire for transparency by the producer.

Details about the olive variety and the location of the producer provide insight into the product's authenticity and quality.

• the varietal of olive (or olives) in the oil eg Arbequina, Picual, Koroneiki and so on. If this info is not clear then the EVOO could be adulterated with cheaper olive oil. Sadly that happens all too frequently - and has happened here in NZ too with some high profile local brands.

• the taste profile. There is a world of flavour in extra virgin olive oil, with multitudes of varietals, styles, aromatics, and indicators of excellence. However there are just four base flavour profiles:

• Intense green fruitiness
• Medium green fruitiness
• Mild green fruitiness
• Ripe fruitiness

• figure out whether the oil is single estate or otherwise. There are many co-ops that produce exceptionally good EVOO blends too, in which case they will provide the info noted above about varietals, FFA levels etc. Always check the details of a blend and whether it's a trusted brand, because blends can cover shady practices.

As background, also consider these factors:

• There are hundreds (around 800) of olive varieties, with around about 100 popularly used to make olive oils. Each has its own taste and sensory characteristics. The 'terroir', the care of the grove, the soil and plant health - dozens of factors determine the quality. A premium EVOO can be made with just one variety (monovarietal) or be a blend. 

• Premium extra virgin olive oil is the best: studies have shown replacing less healthy fats (like seed oils and butter) with just 2 tablespoons of EVOO per day improves health.

• Producing premium extra virgin olive oil is a complex, highly skilled and costly task. For example, early harvest green olives offer more healthy phenols (and extends shelf life), but give significantly less yield than riper black olives that have lost - or oxidised - many of their healthy compounds.

So if a producer is using, say, 12 kgs of green olives to make 1 litre of extra virgin olive oil, it makes sense it will cost a lot more than someone using 4-5 kgs of riper black olives to obtain 1 litre.

• EVOO is extremely sensitive to light and oxygen, so  pay attention to the bottle. Look for packaging that protects the oil. (As well, bulk consumer olive oils are sent through standard container shipping channels with no control over temperature, whereas we prioritise chilled sea freight for all our products.)

The optimal choices are dark glass bottles, tin containers or other opaque packaging. For clear bottles, added outer packaging is required. Check for bottles with a tight seal to avoid air exposure. After opening, store the oil in a cool, dark spot, and ensure it's tightly sealed to limit exposure to oxygen.

• Remember, certification is the key.

And top EVOOs will also have seals from reputable organizations. Credible awards. And certification for protected regional production (for example, the European Union “Protected Designation of Origin” program - PGI, PDO - which certifies the olive oil has been produced in the specified region, typically according to the region’s required methods.) These all serve as an additional control mechanism of quality and adherence to specific production standards.