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Selecting olive oil

Selecting Olive Oil

There are many varieties of olive oil, but not all are created equal. Olive oil is classified into different types that correspond to various quality and commercial standards. In Europe, olive oil is classified by the EU (EC Reg. 1513/2001) according to analytical parameters, its method of extraction and acidity: extra virgin olive oil, virgin olive oil, lampante olive oil, refined olive oil, olive oil, crude olive pomace oil, refined olive pomace oil and olive pomace oil. 

Among them, extra virgin olive oil has the highest content of healthy polyphenols, as well as the highest nutritional value. In addition, scent, fluidity and taste also make extra virgin olive oil stand apart from other types of olive oil as a highest-quality condiment.


The Olfactory test is the best method to evaluate how good an extra virgin olive oil is, meaning that the quality may be effectively determined by its smell. A fresh scent of olives or olive leaves, as if just cut from the olive tree, should be detectable when you smell the oil. The aroma  is different from edible olives. When smelling high-quality extra virgin olive oil, you may find notes of  freshly cut herbs, a leaf rubbed in your hands, a green tomato, an apple or an almond.


By pouring olive oil into a glass and shaking it, one can observe its viscosity. Extra virgin olive oil has a medium to low fluidity, while high fluidity is typical of high-grade saturated fatty acids. The more the saturated fatty acid content, the more the cooking oil can damage your health, so we should try to pick oil with low-mobility. The lower the saturated fatty acid content, the lower fluidity the extra virgin olive oil possesses.


Taste is one of the best ways to determine whether extra virgin olive oil is of high quality. On the palate, the oil should be bitter and slightly spicy. It should also cause a pinching feeling in the throat, which is  due to the presence of the natural polyphenols antioxidants present in extra virgin olive oil. 

To conduct a tasting, a sip of extra virgin olive oil – 1/2 to 1 teaspoon is enough – should be placed on both the tongue and palate. Next, suck in some air through your mouth. There are various ways of doing this, but the goal is to spread the oil around the mouth in addition to the air helping to bring out more flavours. Breath out through your nose and with your mouth closed, to send the aromas into your nasal passages. Savour the oil for at least 20-30 seconds. This way, you can easily evaluate its smell, taste and tactile sensations (bitterness, spiciness and astringency).

Logos to check when purchasing olive oil

In order to ensure the quality of the olive oil and other agricultural products, the EU created PDO and PGI certifications to  make sure that a product produced in a particular area can be recognised on the market.


PDO, or ‘Protected Designation of Origin’, is written as ‘Denominazione di Origine Protetta’ (DOP) in Italian. Only olive oils with excellent quality and credibility can obtain a PDO certification. Olive oil that qualifies for the PDO logo must be grown, produced and bottled in the designated area. It also must meet strict requirements in terms of variety, method of production and overall quality.


PGI, or ‘Protected Geographical Indication’, is written in Italian as ‘Indicazione Geografica Protetta’ (IGP). This certification usually belongs to a larger geographical area, and has slightly less stringent requirements than PDO. Olive oil with the PGI mark must have a feature that is relevant to a PGI certified area, although the link to the geographical area may be limited to a single production phase (for example, growing or processing the olives).

Organic olive oil

An olive oil certified as organic olive oil must be cultivated without the use of synthetic chemicals or GMOs (genetically modified organisms). Only organic matter and minerals can be used for fertilisation.

How to store olive oil

Even the finest quality extra virgin olive oil can go bad if not stored properly. The three main enemies of olive oil are light, heat and oxygen, which all speed up the oxidation process. But there are a few simple steps you can take to preserve the healthy nutritional properties along with aroma and flavour of your olive oil.

1. Protect from light

Prolonged exposure to natural or artificial light (including halogen and fluorescent lights) can not only diminish the taste of olive oil, but also reduce its vitamin and antioxidant content in a process called photo-oxidation. For this reason, it’s best to store your olive oil in a cool, dark place.

The best types of packaging for extra virgin olive oil are dark glass bottles (glass does not alter oil’s taste and is easily recyclable) or stainless steel containers that shield the product from light. Steer clear of transparent glass or plastic containers, as they let in too much light. Read more on how to recognize high-quality olive oil.

2. Keep away from the stove

While it may seem convenient to keep your olive oil by the stove when cooking, hot temperatures can actually be bad for your oil. The ideal temperature for storing olive oil is between 12° -18°, so keep it in a cool place or the lower shelf of a cupboard, away from electric appliances and lamps that can heat the air.

3. Reseal after each use

Rich in natural antioxidants, extra virgin olive oil is relatively resistant to oxidation and does not go off quickly. However, once you open the container, it’s inevitable that the oil will go bad over time through contact with the air. After each use, remember to seal the container with an airtight cap to minimize contact with oxygen. For the same reason, avoid keeping olive oil and olive oil-based salad dressings in clear glass jars and serving cruets that cannot be reclosed, unless it is for immediate consumption.

4. Consume within a few months after opening 

Extra virgin olive oil is a delicate product that does not improve with time. To reap the maximum health benefits from your oil, try to enjoy it within a few months after opening. The best strategy is to buy smaller amounts of olive oil (for example 0.5l) and make sure you are using at least two table spoons of it with your daily meals. If cooking with olive oil is still a new thing for you, look for inspiration in our ‘Food with olive oil’ section

5. Remember the 18-month shelflife

When stored in proper conditions in a cool, dark place, an unopened bottle of olive oil can maintain its optimal freshness for 18 months from the bottling date on the label. But why wait for a special occasion when you can start enjoying its delicate taste and health-inducing properties today?

How to recognise high-quality olive oil

When choosing olive oil in a supermarket or online shop, the profusion of brands, labels, and prices can feel confusing. How do you recognise high-quality products and tell them from the less healthy ones? Here are some simple tips to help you make a well-informed choice:


1. Packaging matters

The best packaging for extra virgin olive oil is an amber or green glass bottle (glass does not alter the taste of the product and is recyclable) or a stainless steel container that protects it from light. Long-time exposure to natural or artificial light (including halogen and fluorescent lights, often used in big stores) may compromise olive oil’s taste and destroy some of its health-inducing properties in a process called photo-oxidation. For this reason, it is best to steer clear of olive oil in a transparent glass or plastic containers. 

2. Always read the label

According to the EU Regulation, olive oil labels must include certain information, such as its net weight, country of origin, expiry date, nutritional values and storage conditions. Look out for this information - if there’s something missing on the label, it means the quality of the oil isn’t guaranteed. Read more about certification and label terminology.

Optional information on the label may include:

  • "first cold pressing" / "cold extract";
  • Characteristics of taste and smell;
  • Acidity (maximum of 0.8% for extra virgin olive oil);
  • Harvesting date

3. Best before date

‘The fresher, the better’ is the basic rule when selecting olive oil. Always pay attention to the ‘best before’ date or harvesting date on the label. Extra virgin olive oil should be pressed within 24 hours of harvesting and bottled soon afterwards. When stored in optimal conditions (protected from light, heat and oxygen) extra virgin olive oil can maintain its freshness for 18 months of its bottling. Read more about how to store olive oil.

4. Is it extra virgin?

Extra virgin olive oil is the healthiest of all olive oil types available on the market. It is cold-pressed from fresh olives without any chemicals being used in the process. This is essential to preserve its precious phenolic antioxidants, as well as its characteristic taste, look and smell. If the label simply says ‘olive oil’ or ‘pure olive oil’, it means the product is a blend of lower quality refined oils and virgin olive oils. Read more about .different types of olive oil.

5. EU quality certifications

The European Union can grant certain official certification seals to some olive oil brands as a guarantee of their high quality. These seals assure that the product comes from a designated region that specialises in producing oils, and meets EU standards. There are three types of EU quality seals:

  • PDO, or the “Protected Designation of Origin”
  • PGI, or the “Protected Geographical Indication”
  • Organic Olive Oil, which guarantees ecological, chemical- and GM-free production

Read more about certification and olive oil quality.

6. Traceability: From tree to table

Some extra virgin olive oils bear a special traceability label (such as a QR code) which can be used to find out more about the product’s origins with the touch of a button. In effect, the consumer can trace all stages in the oil production chain, from farming and milling to storage and final packaging. As defined by the European Regulation (EC) 178/2002, the concept of traceability helps combat fraud and adulteration in the food industry. Read more about traceability.

7. Try before you buy

If you have a chance to taste the product before buying, it is probably one of the best ways to define its quality. The following sensory characteristics are typical of a high-quality extra virgin olive oil:

  • Smell: fruity, fresh and grassy
  • Fluidity: medium to low
  • Taste: can vary from nutty and citrusy to prudent and spicy. A slight bitter aftertaste that pinches the throat is a good sign – it suggests the oil is high in healthy polyphenols, which have antioxidant properties.

To conduct the tasting like a professional, read ‘How to taste olive oil’.

Finally, while the price of a bottle of olive oil doesn’t tell you everything about its quality, the fact is that high quality olive oil is not cheap. Go with your instinct - if the price seems too good to be true, it probably is.

How to taste olive oil

There are more than 700 olive varieties in the world that are used to produce olive oils with unique taste and flavour characteristics ranging from fruity and nutty to prudent and spicy. The best way to pick your favourite flavour is olive oil tasting, which can also tell you a lot about the quality of the product.

In Europe, in order to be labelled “extra virgin”, olive oil must meet strict standards, set by the International Olive Council (IOC). While the chemical composition of the olive oil is tested in accredited laboratories, its sensory (fluidity, aroma and taste) characteristics must be approved by a panel of professional tasters.

However, you don’t need to be a professional to recognise a high-quality olive oil. Nowadays, some European supermarkets are opening their own ‘olive oil bars’, offering customers a degustation of different olive oil samples. If your local supermarket doesn’t provide such an opportunity, why not try it yourself at home? Focus on these key factors to carry out your tasting like a professional:

Appearance: Colour and fluidity

The colour of olive oil is not indicative of its quality. It may vary from dark green to golden yellow, depending on the climate and the ripeness of the olives. Therefore, professional olive oil testers use standard cobalt blue glasses to disguise the colour of the product.

The fluidity of the oil may tell you more about its composition. To test for fluidity, pour about two tablespoons of oil into a glass beaker, swirl it around, then hold it up to the light to observe the viscosity of the oil. Extra virgin olive oil has a medium to low fluidity and appears thicker due to a high amount of healthy monounsaturated fatty acids. In contrast, higher fluidity is associated with polyunsaturated fats, found in lower quality olive and seed oils. Read more about olive oil types.

Smell: Fresh, fruity and grassy

The smell of high-quality extra virgin olive oil is fruity, fresh and grassy. It may remind you of freshly cut herbs, a leaf rubbed in your hands, a green tomato, an artichoke, an apple or an almond. Any oil that has an unpleasant rancid, mouldy or metallic odour is most likely defective.

Before the olfactory test, warm a glass containing the oil in your hand, while covering the top with the other hand to maximise the volatile aromatic components. Then bring it to your nose and inhale slowly and deeply.

Taste: Bitterness is healthy

The taste of extra virgin olive oil is often reminiscent of fresh olives, with some fruity or grassy notes, and it has bitter aftertastes that should cause a pinching feeling in the back of the throat. However, the bitterness is actually a good sign – it indicates the presence of natural polyphenols (antioxidants) that can protect our bodies from oxidative stress, lowering the risks of many chronic diseases.

To conduct the tasting, sip a half- to whole teaspoon of oil and use your tongue to distribute it throughout your mouth. Inhale some air through your mouth and breathe out through your nose to send the aromas into your nasal passages. Savouring the oil for 20-30 seconds is enough to be able to evaluate the different aspects of the taste (bitterness, spiciness, and astringency).

This tasting technique takes practice, but it should help you to identify the flavours in different kinds of olive oil. Once you’ve chosen your favourite, it’s time to get cooking and enjoy new gourmet experiences in your kitchen using olive oil. Read more about food with olive oil