Food
Olive oils
Introduction
Extra-virgin olive oil is the highest-quality olive oil you can buy. But we found many that weren't worthy of the "extra-virgin" tag.
We put 21 extra-virgin olive oils from New Zealand, Australia and Europe through a chemical test, and also asked a panel of expert tasters to assess their quality.
Find out which 3 oils rated best and earned our recommended tick.
Products we tested
Our panel tasted 21 extra-virgin olive oils from supermarkets and specialist food stores. Seven were made in New Zealand, one was imported from Australia, the rest were from Europe.
- Borges (Spain)
- Cinderella (Spain)
- Colonna (Italy)
- De Cecco Classico (Italy)
- Kapiti Leccino/Frantoio (New Zealand)
- La Espanola (Spain)
- Lepanto (Greece)
- Lupi (Italy)
- Mas Portell Arbequina (Spain)
- Olivo (New Zealand)
- Pams (Spain)
- Paul Holmes Leccino (New Zealand)
- Peta Mathias (New Zealand)
- Ravida (Italy)
- Rizzoli (Italy)
- Romulo Arbequina (Spain)
- Select Signature Range (Australia)
- Select Woolworths (Italy)
- Simunovich Olive Estate (New Zealand)
- The Village Press Frantoio (New Zealand)
- Tussock Blend (New Zealand)
Our tasting
You can pay top dollar for extra-virgin olive oil. But the best indicator of a good oil is freshness - the top oils in our tasting were pressed this year.
Extra-virgin olive oil is produced without heat or chemicals. The International Olive Council (IOC) says that extra-virgin oil must meet certain analytical criteria and be free of defects when the oil is tasted by a sensory panel trained to IOC standards.
We were looking for well-balanced oils that had good aroma and flavour - and no defects. Colour has nothing to do with the quality of olive oil. Oils are tasted in blue glasses so the colour is masked.
We were disappointed in the overall results. Too many oils (mainly imported) fell into the "unacceptable" category when tasted. Retailers and importers need to do a better job of packaging and displaying extra-virgin olive oil.
Packing it in clear bottles and exposing it to artificial light for long periods will only result in the oil deteriorating.
Extra-virgin olive oil is an expensive semi-luxury product. It should be looked-after better so that consumers receive the quality product they're paying for.
Kiwi oils come out top
All the oils passed the chemical analysis we put them through, but there was a wide range in their sensory quality.
Fresh is best! The three top oils in our tasting were pressed in May or June 2008.
The Peta Mathias (pictured), Olivo and The Village Press Frantoio oils all had the qualities our judges were looking for - good aromas with lots of olive fruity flavours. They were also well balanced.
These three oils were also in dark bottles, which are better protected from the light. Clear bottles are a problem, especially in supermarkets where the oils sit under fluorescent lights. Some supermarkets are open for 24 hours and this increases the light-exposure.
The Borges, Pams and Paul Holmes Leccino oils were also very good. But the Borges and Pams had no date marking. We may have struck a fresh batch of these but there's no way of knowing - and other Borges and Pams on shop shelves may be older.
Tired oils
The most common complaint about the unacceptable oils was that they were tired. Tired oils taste "old" and not fresh - it's a sign an oil is starting to go rancid. But many oils don't give you enough information on the labels to judge.
Most oils state a best-before date, although that's no guarantee of quality. Many of the unacceptable oils were well within their best-before date. Colonna, La Espanola and Mas Portell Arbequina were judged unacceptable even though they had best-before dates in 2010 - that's over a year away.
The problem with best-before dates is you don't know how old the oil is. Six oils stated their pressed-on date. This is more helpful because you know exactly how old the oil is. We'd like to see pressed-on dates for all extra-virgin olive oil.
Some oils didn't do as well as they did in our 2006 tasting. Kapiti was one of our top oils in 2006 but this time our panel rated it poorly. The producers are concerned that their oil isn't being stored properly in shops and is following up this issue with retailers.
Ravida also got a lower rating. The importer told us the size of Ravida shipments has been reduced to ensure a fresher product in New Zealand.
Our tasting panel
- Margaret Edwards (senior judge) - Vice President of Olives NZ. Leader of the Olives New Zealand tasting panel.
- Franca Camurati (senior judge) - Chemistry consultant and judge for the International Olive Council. International olive oil judge. For seven years panel leader of the Italian Institute for Fats and Oils tasting panel.
- Roberto Zecca (senior judge) - International olive oil judge. Former President of California Olive Oil Council. Former panel leader of California IOC panel. Olive oil producer in Tuscany and California.
- Laurence Eyres - Chairman of the New Zealand Institute of Chemistry Oils and Fats Specialist Group. Business Development Manager, Food and Nutrition, University of Auckland. Food Standards Australia New Zealand board member.
- John Follas - A food and wine importer. Owner of specialist food store Truffle.
Consumer tastings differ from industry tastings and competitions. We buy our oil from shops just like consumers do - most other tastings and awards use oil supplied by manufacturers or importers. Our panel members tasted the oils "blind".
With a panel of five judges it's difficult to get consistent ratings. If one judge gives a low score this affects the overall score. For our tasting we only counted the scores of the three senior judges. Our three senior judges have all been trained to IOC standards.
In some cases we may have bought old stock or oils that hadn't been stored properly. Either of these reasons may account for the poor rating our panel gave some oils.
The chemical test
According to International Olive Council rules, extra-virgin olive oil must have a maximum free fatty acid (FFA) level of 0.8 percent and a maximum peroxide value of 20.
The FFA level measures the amount of chemical breakdown of the oil. This tends to increase as the fruit ages - and also between harvest and process - but it's fairly stable once the oil is bottled. There's little connection between FFA levels and flavour.
The peroxide value (PV) measures the level of oxidation at any given time. It's affected by air or light coming into contact with the oil during processing and storage. The peroxide value can continue to rise in the bottle over time.
Beyond the technical ...
All the extra-virgin olive oils passed the chemical analysis, so why did our tasting panel pick up defects in 10 of them?
When an olive is picked, it has a PV of almost zero. A good olive oil pressed promptly under good conditions will end up in the bottle with a PV of 2 to 3. But there's still oxygen in the bottle - and so the oxidation process begins.
When oil reacts with oxygen it begins to deteriorate. The PV will increase in the bottle, with the peroxides breaking down to give nasty-smelling and nasty-tasting compounds.
Light also speeds up the oxidation process. "Off" flavours will be evident even at low PV values, if the oil has been exposed to light. But because most people don't sip and suck olive oil from a glass (as our tasters did), these faults are often difficult to pick.
Some in the scientific community are concerned that the International Olive Council's PV maximum of 20 is too high. Olives New Zealand (the New Zealand industry body) agrees.
To qualify for Olives New Zealand certification, New Zealand olive oils must have a PV value of less than 15. They must also be in dark bottles or packaged in a box - and they must show both the year of production and a best-before date of no more than two years after the oil was pressed. Olives New Zealand certification is indicated by a red sticker on the bottle.
Products compared
Guide to the table
Products are listed alphabetically according to their ratings. Price is per 100ml and is based on the price we paid. Larger sizes may be more economical.
= The highest-scoring oils in our tasting.
We recommend
These three Kiwi olive oils were the best in our tasting. They also came in dark bottles and had pressed-on as well as best-before dates.
The Village Press Frantoio
Olivo
Peta Mathias
Buying advice
- Buy the freshest oil possible. Look for a "pressed-on" date, as best-before dates aren't a good indicator of quality. We'd like to see "pressed-on" dates for all extra-virgin olive oil.
- Heat and light will affect oil quality. Don't buy clear-bottled oils, especially ones that have been displayed in a shop window or under fluorescent light.
- Store in a cool dark place, tightly stoppered. Once bottles are open they are best stored in the fridge. The oil may become cloudy or solid. This won't affect the taste and it will clear when brought to room temperature.
- Oils don't improve with age - use them as quickly as you can.
Country of origin
Buying extra-virgin olive oil from Italy? You need to check the labels carefully - chances are it's not made from Italian olives at all.
Spain is the biggest producer of olives and olive oil. Italy is the second-biggest producer. But, because the Italians are the biggest consumers of olive oil, Italy doesn't produce enough olives to meet local demand. A lot of the Spanish crop is exported to Italy, where it's repackaged for sale as Italian olive oil. Other countries such as Greece and Turkey also export olives to Italy.
Lupi says it's "imported from Italy". This gives the impression that the olives were grown in Italy but it probably only means the oil was bottled there. Rizzoli is a bit more upfront - the label says it's "bottled in Italy".
If you're looking for olive oil made with Italian olives look for the label "Product of Italy" or "Produced and bottled in Italy".
All about oils
Olive oil has a long history as "the good oil". One hundred years ago the New Zealand Herald published an article about the European medical profession using olive oil for many childhood diseases, such as measles and scarlet fever.
Its reputation is still well deserved, for different reasons. All types of olive oil contain high levels of monounsaturated fats, which help lower your blood cholesterol and reduce your risk of heart disease when you consume them rather than saturated or trans fats.
Extra virgin has an advantage over other olive oils. When processed correctly it contains the highest levels of antioxidants and polyphenols. Antioxidants appear to protect the body from age-related changes and certain diseases, such as heart disease and some cancers. Of all antioxidants, polyphenols have the most effect.
Despite the health benefits, remember that any oil is 100% fat. If you eat too much of it, you may put on a few extra kilos.
Different grades
- Extra virgin is the highest grade of olive oil. It's made with minimal processing to maintain flavour and aroma. It can't have more than 0.8% acidity and must be fault-free as assessed by an expert panel.
- Virgin is olive oil with minor imperfections and a higher acidity level (up to 2%).
- Pure is refined olive oil with a small amount of virgin oil added, resulting in a milder olive taste.
- Light or extra-light is refined olive oil. It's light in colour and taste. But it's no lighter in fat or kilojoules than other olive oils.
The right oil
When you buy cooking oil you need to consider what you'll use it for - and its taste. You shouldn't use your pricey extra-virgin olive oil for bangers on the barbie.
For everyday cooking or the barbie you'll want a neutral-tasting oil which doesn't mask the flavour of your food. Regular refined olive oil and canola are good choices.
For frying, you'll need oil with a high "smoke point". The smoke point is the temperature to which the oil can be heated before it smokes and discolours. Best oils for frying are blended vegetable oils, sunflower, grapeseed, and peanut oil.
For salads, pasta and stir-fries you may want oil with a distinctive flavour. Most cold-pressed oils (extra-virgin olive, almond and avocado) are good choices. They are also great drizzled on meat, fish, vegetables and salads, or for dipping bread.
When good oils go bad
Defects can occur because of mishandling during and after harvest, and during processing, bottling and storage. They lead to unacceptable aromas and flavours in the oils. Some of the common defects are listed below.
Fusty: This is a defect characteristic of olives that have been stored in piles for too long before processing. The aroma is similar to old or decomposing olives.
Metallic: The flavour found in oils extracted with both new processing plants and/or used for the first time at the beginning of the processing season.
Muddy sediment: The oil may have been left in contact with sediment and water that settles in tanks and vats.
Musty: This is a mouldy flavour, caused by mould growth on olives stored in piles in humid conditions for several days before pressing.
Rancid: Rancidity is a common defect. It is elevated during improper storage or transport, at high temperatures, when stored in sunlight, and once the oil has been opened and exposed to air. Over time, rancidity increases - the oil may have deserved the extra virgin tag when bottled but it hasn't stood the test of time.
Winey: A winey or vinegary flavour mainly due to fermentation from the growth of yeasts during poor storage of the olives.
Olive oils can also be tired or flat. Tired oils taste "old" and not fresh - it's a sign an oil is starting to go rancid. Flat oils have a weak flavour and aroma, often from the loss of fruitiness of the oil. New Zealand olives may suffer frost damage. This can affect the oil. There may be flavour changes from a loss of flavour and aroma.
Report by Belinda Allan.