You are at the supermarket, standing in front of shelves full of olive oils. You pick one bottle, stare at it, put it back, and you pick another up. Which one have you finally decided to buy?
The right question we should ask ourselves is: What are we looking for in the first place? Only by answering this question will we be able to make an informed decision when buying quality extra virgin olive oil.
You will find eight tips by the end of this article to help you decide. But before that, some general knowledge to level up our understanding of the extra virgin olive oil.
Back in the old days dated thousands of years ago, olive oil was made by grinding the olives into paste using large millstones and then pressing the olive paste to separate the liquid oil and vegetation water from the solid material to make the first cold-pressed olive oil. No heat nor chemicals were administered to extend or alter the oil.
In the second pressing, the paste was then mixed with hot water or steam and pressed again to remove more oil. The second press will not be as good as the first because the heat had already evaporated some of the delicate flavours and healthy components naturally found in the olives.
Is Cold-Pressed an Accurate Term to Use?
Nowadays, olive oil is mechanically pressed and made in centrifuges under a temperature-controlled setting of not exceeding 28oC. Hence we may sometimes see these words on the label which state “olive oil obtained directly from olives and solely by mechanical means.”
Some profit-oriented olive oil producers may resort to adding water during the oil extraction process to seek greater oil outputs. This may result in the lost of the important phytonutrients in olive oil.
As for oils still made using the traditional presses, they would be as good as the mechanically pressed ones as long as strict hygiene conditions are met during the production.
Some of these conditions include cleaning of the mats which could be a difficult task, removing the chemicals left behind which are responsible for winey and fusty defects, and reducing the exposure with oxygen in the open environment where the olive paste is being pressed.
Therefore, “cold extraction” is a better term to depict how olive oil is extracted from the olives today and, to a certain extend, it represents the quality standard of the extra virgin olive oil.
Furthermore, the production of extra virgin olive oil should only come from the first press, and never the second. So the term “first” in “cold-pressed” is redundant.
It is not the term that really matters. What matter most is the flavour and aroma.
To select a good quality extra virgin olive oil, ask for a chance to taste the extra virgin olive oil prior to purchasing.
The basic idea behind expeller-pressed oil is to force-press oil out of nuts, seeds or vegetable like corn through mechanical strength.
Expeller-pressed oil is often very similar to cold-pressed oil in that neither involves the use of any chemicals. The difference lies in cold-pressed method is operated under a temperature-controlled setting usually within 28oC, whereas expeller-pressed oil is processed at higher temperatures that may reach around 95oC.
These expeller-pressed oils sold in our supermarket are “refined for high heat”. What it means is that the oil has been processed to remove impurities, making them more stable, especially for higher-temperature cooking. However, the process of refining also filters out much of the flavour and nutrients.
Because cold-extracted oil is processed at lower temperatures, it retains a higher phenolic and nutrient content than expeller-pressed oil.
OLIVE OIL GRADES
We see these words all the time printed on the label of the bottle: extra virgin olive oil, pure olive oil, extra light olive oil, and recently even olive-pomace oil.
This classification denotes the quality of the olive oil and indicates the typical usage in our culinary preparation.
- Extra Virgin Olive Oil is often called the “olive juice” because it is obtained directly from the olives without using heat and chemicals during the extraction process. For olive oil to qualify as “extra virgin”, it must have a superior flavour and aroma, and its Free Fatty Acid must fall below 0.8% by the International Olive Council standard.
A premium quality extra virgin olive oil typically has Free Fatty Acid less than 0.3%.
- Virgin Olive Oil has a Free Fatty Acidity of not more than 2%. It is judged to have a good taste, but may include some sensory defects with enough flavour to be enjoyed uncooked. This type of olive oil is not available locally but abundant in Europe such as Spain. It is often used for frying due to its value-for-money and good nutritious values.
Extra virgin olive oil can be used for low to medium temperature frying not exceeding 190oC.
- Pure Olive Oil / Extra Light Olive Oil is made from a blend of refined olive oil and (extra) virgin olive oils normally in the ratio of 90:10. This type of oil has undergone an extremely fine filtration process without the use of heat or chemicals to remove most of the natural colour, aroma, and flavour. It has a Free Fatty Acidity of not more than 1%. This type of oil withstands heat well, and therefore it can be used for deep frying.
When we take two tablespoonful of a premium quality extra virgin olive oil directly, not only we will not feel any greasiness, but also we will have already had a day of anti-inflammatory and antioxidants needed by our body.
- Refined Olive Oil is the olive oil obtained from poor quality virgin olive oil that has a high acidity level and/or organoleptic defects. The virgin olive oil is then undergone a refining methods to reduce the acidity and sensory defects, but it does not alter the initial glyceridic structure – that means it still retains the monounsaturated fatty acid. However, it has little phytonutrients (anti-inflammatory and antioxidants), and it is flavourless and odourless.
Over 50% of the olive oil produced is of poor quality that must be refined to produce an edible product.
Tom Mueller, author of Extra Virginity: The Sublime and Scandalous World of Olive Oil, has this advice to the consumers, “high prices don’t guarantee great oil, low prices – under about US$10 for a liter – strongly suggest that the oil you’re buying is inferior.” He said, “producing genuine extra virgin oil is expensive.”
- Olive-Pomace Oil is a blend of refined pomace olive oil and (extra) virgin oil. Refined pomace olive oil is produced from the leftover olive pastes using the same chemical solvents and refining methods used for seed oils such as canola, sunflower and peanut, and hence this type of oil cannot be called “olive oil.” However, olive-pomace oil has the same fat composition as regular olive oil giving it the same health benefits. It is fit for consumption. It has a high smoke point, hence perfect for deep frying.
Best extra virgin olive oil is made with olives that come from the same olive grove, produced in the mill of the country of origin and within the olive grove proximity, and the olive oil is cold extracted within 24 hours upon picking.
Next time when you pick up one bottle of extra virgin olive oil, scrutinise the origin of the olives and the production mill, as well as look for “extra virgin olive oil” in the ingredients section.
CHEMICAL QUALITY TEST
It is not surprised to find some of the most important quality parameters of extra virgin olive oil not printed on the label. This could be due to two reasons.
One reason is that the label is already pre-printed with information that is not dependent on the harvest season – just like wine, the quality of extra virgin olive oil depends on the health of the current year’s crops. The second reason is because the quality parameters are too technical for most of us to understand.
Whatever reason it may be, please ask for the chemical quality parameters from the olive oil suppliers.
What Are These Chemical Quality Parameters?
- Free Fatty Acid (FFA) is a general measurement of olive oil quality. The higher the FFA > 0.5%, the higher the probability of having taste defects. Extra virgin olive oil with low FFA will also smoke at a higher temperature (between 190-215oC).
FFA are fatty acids which have broken away from oil molecules (triacylglycerols) during extraction.
Factors which lead to a high FFA in an oil include fruit fly infestation, delays between harvesting and extraction, especially if the fruit has been bruised or damaged during harvesting, fungal diseases in the fruit, prolonged contact between oil and vegetation water after extraction, and careless extraction methods.
- Peroxide Value (PV) measures the amount of primary oxidation in the oil. High values are caused by improper handling of the olive fruit or olive paste. Peroxides have no flavour and are generated from the oxidation of polyunsaturated fatty acids in the oil. High temperature, light and oxygen exposure lead to the generation of peroxides. When this happens, the olive oil has a musty/rancid oil smell. The PV set by the International Olive Council for the extra virgin olive oil is less than 20 meq O2/kg. Premium quality extra virgin olive oil has PV less than 9 meq O2/kg.
Peroxides are unstable. Olive oil with high peroxide value may not keep well.
To reduce peroxide levels and therefore delay oxidation of high peroxide oils, suppliers opt for blending of different oils or refining to eliminate peroxides and remove off-flavour substances. The resulting product will not be extra virgin olive oil.
- Ultraviolet (UV) Absorption is a secondary measurement of rancidity in oil. A high absorption value indicates that the olive oil lacks freshness and has oxidised and/or is a poor quality olive oil, possible refining and/or adulteration with refined oil. The standard is K270 ≤ 0.22.
Superior extra virgin olive oil will have K270 ≤ 0.20. Low values correlate with high-quality oil, as UV absorption detects early and later states of oxidation.
- Wax Content: Olive trees produce a natural thin layer of wax on the surfaces of the olives to keep in the moisture when things start to heat up in the semi-arid conditions. When olives are processed into oil, the oil that is released dissolves the skin waxes and it ends up in the oil. Wax content is an indicator of the level of adulteration with pomace oil, because pomace contains a greater proportion of fruit skin where most of the waxes originate. The International Olives Council limit for extra virgin olive oil is less than 250 mg/kg.
Cold climate extra virgin olive oil on average has a wax content of less than 45mg/kg, while hot climate extra virgin olive oil 115mg/kg.
While the amount of wax in an olive oil is pretty small, its presence probably acts as a seed for cold solidification.
SENSORY TEST: AROMA & TASTE
Extra virgin olive oil must be found to be free from sensory defects and exhibit fruitiness.
We can do two things to test the aroma and taste. First, smell it with our nose. Second, take a sip into our mouth.
- Smell: Pour a little bit of olive oil into a small wine glass. Cover the opening with one palm and place the other at the bottom of the wine glass to warm it up. Hold it, swirl it, warm it for a minute or two. Then stick our nose into the glass and take a good whiff of the aroma of the olive oil. The extra virgin olive oil must exhibit the smell of fresh-cut grass, or have the aroma of ripe or green olive fruit.
- Sip: Take a sip of the oil, enough to cover our entire mouth and tongue. Suck air through the oil to coax more aromas out of it, and then close our mouth and breathe out through our nose. We must notice the flavours it exhibits. Now swallow some, or all of the oil. It may give out the pungency when it reaches at the back of our tongue.
Olive oil Master Tasters would describe the positive attributes of an extra virgin olive oil using the following terminologies:
- Fruity: It depends on the varietal, the olive oil must have pleasant spicy fruit flavours characteristic of either fresh ripe or green olives. Ripe fruit yields oils that are milder, aromatic, buttery, and floral. Green fruit yields oils that are grassy, herbaceous, bitter, and pungent.
- Bitter creates a mostly pleasant acrid flavour sensation on the tongue. Olive taste bitter right off the tree, and hence an extra virgin olive oil that has bitterness is considered fresh. Olive oil made from riper fruit will have little to no bitterness, oil made from greener fruit can be distinctly bitter. Extra virgin olive oil with a high polyphenol content, a natural antioxidant, tends to be more bitter.
- Pungent is a peppery sensation in the back of the throat. Pungency is a positive characteristic of olive oil. It can be very mild or it can be intense enough to make us cough. Green, early harvest, olives tend to yield pungent oils that can cause a one, two or three cough reaction when tasted.
The International Olives Council also identifies some common flavour defects in an extra virgin olive oil. Any detection of even the slightest amount of any of these defects will disqualify the oil from achieving the highest grade of Extra Virgin.
- Fusty/Muddy is a common defect that appears when the olives are gathered in piles and may cause advanced fermentation. According to an olive oil consultant, Alexandra Kicenik Devarenne, fusty smells like or tastes like sweaty socks or swampy vegetation.
- Musty/Earthy characterised oils obtained from fruit in which large numbers of fungi and yeasts have developed as a result of its being stored in humid conditions for several days or of oil obtained from olives that have been collected with earth or mud on them and which have not been washed.
- Winey/Vinegary characterised certain oils reminiscent of wine or vinegar. This flavour is mainly due to a process of aerobic fermentation in the olives or in olive paste left on pressing mats which have not been properly cleaned and leads to the formation of acetic acid, ethyl acetate and ethanol.
- Rancid is the most common flavour defect of oils which have undergone an intense process of oxidation, i.e. it is basically olive oil gone bad. Rancidity taste like eating old nuts or stale crackers that are made with fat.
- Metallic: A taste that reminds of metal. Usually it is a result of prolonged contact with metallic surface during production but also storage.
8 TIPS TO CHOOSING GREAT EXTRA VIRGIN OLIVE OIL
Olive oil is a major component in the Mediterranean diet and has been widely considered to be one of the world’s healthiest foods.
Some of the proven health benefits of olive oil include preventing heart disease, reducing the risk of Alzheimer’s disease and Type II diabetes, protecting our heart and certain kind of cancers, decreasing the risk of depression, and other health benefits.
The health benefits of extra virgin olive oil come from the phenolic compounds, Oleocanthal, Oleacein, Oleuropein, and Hydroxytyrosol.
These compounds are also major contributors to the flavour of the oil.
Oleocanthal gives us the peppery or burning sensation in the back of the throat, Oleacein is pungent, and Oleuropein is very bitter.
According to Tom Mueller, an investigative journalist who wrote the book entitled, Extra Virginity: The Sublime and Scandalous World of Olive Oil, 70% of the extra virgin olive oil sold in the world is adulterated.
How Then Should We Choose an Extra Virgin Olive Oil That is of High Quality?
Here are 8 tips to choosing a high quality extra virgin olive oil:
TIP #1 – Choose Extra Virgin Olive Oil & Read the Label for the Harvest Date, Place of Origin & Cultivars
The label must include at least three essential elements to speak well on the quality of the olive oil, according to an olive oil expert, Nicholas Coleman:
- Harvest date or at best production date,
- Specifically where the olives are grown and the olive oil produced, and
- Cultivars (types of olives) that made the olive oil.
A general rule of thumb is, the fewer the sources of olives used to make the olive oil, the less time the olives spend in transit, being handled, packaged, and processed. The quality of the olive oil is correlated to the delay between harvest and production.
Be wary when we read the label with the phrases like “packed in” or “bottled in.” This means that the olive oil is neither made in nor contains olives of the said country. Generally, avoid olive oils that do not specify the production mill on the label.
Choose extra virgin olive oil over “pure”, “extra light” or “pomace” olive oil as the former is a natural fruit juice, which is the highest quality grade among the olive oils.
“Pure”, “Extra Light” or “Pomace” olive oil is a refined oil. It does not have olive flavours and many of the oil’s health benefits have been stripped away during the extraction process. They are good for high-temperature deep frying, however.
To ensure freshness of extra virgin olive oil, look for bottles with a “Best By” date, or at best that display the harvest date.
Unlike wine, olive oil does not improve with age. The flavour and aroma of extra virgin olive oil are at their peak when it’s young and will begin to deteriorate over time, especially when the bottle is opened and the olive oil is in contact with oxygen.
The best-by date is not a foolproof method to choosing the freshest oils as the olive oil may be a blend from different years and are stored in a tank for an extended time before bottled, though the producers have used nitrogen or argon in the head-space of the container to keep the oil stored in the tank away from oxygen.
If we can’t identify the harvest date from the bottle, at least we should choose an extra virgin olive oil with a best-by date within two years period. We should always avoid purchasing olive oils that are displayed under direct sunlight or in an overly warm environment.
Pure Olive Oil is a lower grade, explained Dan Flynn, Executive Director of the University of California Davis Olive Center.
Refined oil doesn’t mean elegant or high class, and he said, refined olive oil has been processed with solvents to mask off odours and flavours.
TIP #2 – Check for a Seal of Approval
It is very difficult to obtain a D.O.P. certification. Extra virgin olive oils that are endorsed by D.O.P must adhere to a specific specification and are subjected to the control of an independent certification body who is specially appointed and recognised by the Ministry of Agriculture and Forestry.
The specification covers the rules of cultivation, harvesting, milling, and packaging of olive oil:
- The olives that reach the oil press are of an authorised variety and derive from the olive groves within the D.O. areas;
- The olive oil is produced by a registered press and under the supervision of inspectors nominated by the Regulatory Council and licensed by the Ministry of Agriculture of the Regional Government;
- The olive oil is stored within the D.O. production area, whether the storage be in the olive oil mill or in the bottling plant;
- Physo-chemical and organoleptic analysis are carried out for all components of the olive oil that can be catalogued;
- The olive oil that is bottled and introduced to the market with a guarantee of its origin, a numbered label and the D.O. logo of the Regulatory Council, has passed every quality control at each stage of the production process.
D.O.P. certifies extra virgin olive oil for its quality and origin. The origin requirement stipulates that the olives and olive oils must be produced, processed and prepared exclusively in that region.
Look for extra virgin olive oil that has a D.O.P. stamp on its label.
TIP #3 – Check for the Chemical Quality
The chemical parameters like Free Fatty Acidity (FFA) and Peroxide Value (PV) are often not printed on the label. We should look for them somewhere, at least from the website where the products are sold.
FFA indicates the breakdown of the basic fat structure of an olive oil during the extraction process, whether due to poor-quality olive fruit (bruising, olive fly infestation, fungal attack) or most commonly, by delays between harvest and extraction of the oil.
A low FFA doesn’t guarantee high quality, but a high FFA almost always means poor extra virgin olive oil.
Low acidity indicates good phenolic content in an extra virgin olive oil.
The degradation of these compounds result in rancid taste and a reduction in the smoke point.
The Peroxide Value of an extra virgin olive oil indicates the extent to which a young oil has been oxidised, typically through breakdown by free radicals or by exposure to light.
High wax content indicates that the extra virgin olive oil may have been adulterated with pomace olive oil.
The FFA level set by the International Olive Council for the extra virgin olive oil is less than 0.8% and the Peroxide Value less than 20 meq O2/kg.
TIP #4 – Test the Sensory Quality
Before you purchase an extra virgin olive oil, try to ask for a chance to taste the olive oils. If you are not given the opportunity, ask the suppliers some questions such as how, where and by whom the olive oils were made.
When you can’t taste the oil first, buy from those producers that performs stringent quality control in their production and selection of oils. Ensuring that the extra virgin olive oil has a seal of approval from D.O.P. is a good start.
During olive oil tasting, we should look for the absence of defects. A common defect is fusty, which is the result of olives being piled up and sit around for too long after harvest before they are pressed, and rancid.
Seek out freshness in the extra virgin olive oil, and choose olive oils that smell and taste vibrant and lively. Also pay attention to mouth feel: prefer those that are crisp and clean to greasy.
The best olive oil is bitter, pungent, and burns the back of our throat.
Don’t be put off by bitterness or pungency – these are indicators of the presence of healthful anti-inflammatories and antioxidants.
“Early harvest” oils tend to be “robust” (bitter and pungent), with greener characters such as grassy aromas.
“Late harvest” oils tend to be delicate and mild, with sweeter characters.
TIP #5 – Choose the Award-Winners
Extra virgin olive oils that scored well in recent, reputable olive oil contests are often a good choice as the competition measures the current year’s harvest.
These extra virgin olive oils that took part in the international olive oil competitions have been judged and testified by a panel of olive oil Master Tasters to be superior in their sensory taste.
Leading olive oil contests include but not limited to Sol d’Oro, Mario Solinas, and New York International Olive Oils Competition.
TIP #6 – Prefer Filtered Extra Virgin Olive Oil Than Unfiltered
While improper or excessive filtration can attenuate certain flavours and aromas, the sediments in an unfiltered extra virgin olive oil – that is tiny bits of olive pulp and skin floating in it – may often spoil faster than the olive oil itself, and can produce the taste flaw of muddy sediment.
Filtered extra virgin olive oil has a longer shelf life.
TIP #7 – Decide on the Usage of Olive Oil
When choosing an olive oil, it all boils down to usage; what do we want to do with it? Use it raw, or for frying.
Health benefits aside, the key factors you need to consider are heating temperature and flavour. Oils break down at a certain temperature, which is known as their smoke point.
Extra virgin olive oil is a fine choice for sautéing and low to medium temperature frying not exceeding 190°C, such as frying eggs and vegetables, and so long the olive flavour does not overpower the food prepared.
On the other hand, refined olive oil such as the pure and light olive oils are a better choice for deep or high temperature frying and it is generally tasteless, just like any vegetable or seed oils.
Unrefined oils have lower smoke points than refined oils. They also tend to have a stronger flavour. Refined oils have higher smoke points and typically a more neutral flavour, which makes them better for deep-frying.
Early-harvest extra virgin olive oil tends to be spicy, bitter and pungent, use it uncooked as it has the most health-enhancing and heart-healthy phytonutrients.
TIP #8 – Look at the Packaging
When choosing bottled olive oil, we should prefer dark glass or other containers that protect the oil against light.
Buy a quantity that you will use up quickly, and keep it in a cool and dark place.
Even an excellent olive oil can rapidly go rancid when left sitting under a half-bottle of air, or in hot or brightly-lit conditions.
KNOW WHAT YOU ARE DOING
Extra virgin olive oil is expensive, so know what you are buying.
There are many fake or adulterated olive oils out there. Taste test the extra virgin olive oil for its flavour and aroma if you are new to the brands before you part away with your hard-earned money.
Most of the great extra virgin olive oils may not come from supermarket. Expensive oils from the boutique shops may not be that affordable, and normally they are beyond the reach of many.
You don’t have to dig deep in your wallet to get good quality if you know where to shop for the right olive oil.