June

Olive oil with Maggie Beer

The Slowpoke: GUIDE TO OLIVE OIL

A bottle of olive oil is an essential in many a kitchen. With Australia’s olive harvest season well underway, this year’s fresh oils are on their way too. And given there’s a world of difference between a good (and local) olive oil and a bad one, queen of all things Aussie produce, Maggie Beer is here to teach us how to choose, care for and use olive oil.

“As a flavour-driven person who loves to cook, the only olive oil I use is extra virgin, as I’ve said before. But first let me attempt to explain the difference between the varying grades of olive oil.”

Extra virgin olive oil

Extra virgin olive oil is the oil or juice of fresh olives extracted purely by mechanical means. The crushed olives become a paste and the oil is extracted from this paste without the use of chemicals, and with only enough heat to naturally separate the oil, which is lighter than the water and solids of the paste.
Don’t be misled by the term cold-pressed oil. This term has virtually no relevance in today’s technological age, therefore, if used, it is used incorrectly, and only because it is seen by marketers as being a statement of quality.

To be considered as extra virgin olive oil, on testing the oil must be found to contain less than 0.8 per cent free fatty acids, measured as oleic acid. However, within this definition, there is a huge range of flavour profiles of extra virgin olive oils, from the fruity, aromatic, pungent and yet beautifully balanced, to the other end of the spectrum of mellow and even bland, and everything in between. Knowing that an olive oil is extra virgin should therefore only be the starting point to choosing a good-quality oil.

The level of free fatty acids in olive oil is a result of the degree of ripeness of the olives – oil from early season olives contains the least free fatty acids – and the care taken in handling the fruit between harvest and oil extraction. The quality of an extra virgin olive oil is the result of this, combined with the length of time between picking and crushing, the cleanliness of the olive crusher and the temperature at which the crushing process is carried out. The olive varieties used, as well as the terroir (that wonderful term that signifies the characteristics of the growing environment: the position, soil quality and prevailing weather conditions) also have an impact on flavour and quality. Many producers proudly display just how low a level of free fatty acids their oils contain, often so low as to hardly register – yet these oils, although they will have a longer shelf-life, can lack flavour if picked too early.

With our extra virgin olive oil, we are continually aiming to get the balance right between picking early for longevity, but with sufficient maturity to give flavour. Each year I learn enough to know how much more I need to know. The difference there is in the quality of the oil and its flavour when, having decided that our olives are perfect to pick, I can’t get the picking organised until a week later, astounds me.

Although half-ripe fruit yields less oil, which is less economic for the grower, the resulting oil has greater quality, integrity and longevity. Riper fruit yields far more oil, but results in a rapid decline in quality a few months after harvest, whereas oil made from earlier picked fruit, assuming that it meets all the other necessary conditions for quality, is still fresh and sound a year after harvest.

All of this means that, although an oil could be termed ‘extra virgin’ because of its low level of free fatty acids, if it has flavour defects from processing such as being ‘fusty’, ‘musty’ or ‘winey’ (to name a few), this would deny the oil the extra virgin classification. Even if an oil makes the extra virgin classification because it contains under 0.8 per cent free fatty acids, but is a much riper oil, then it will not have the shelf-life of an earlier picked oil, so it will not necessarily retain its extra virgin status over time, particularly if stored badly. Rancidity, the most common fault in extra virgin olive oil, is usually a fault of bad storage and/or the age of the oil, and is so easy to detect once you’ve identified it – just think of the smell of sweaty socks, or butter left uncovered in the back of the refrigerator that has absorbed every ‘off’ odour around it.

Many people, when first beginning to learn about good olive oils, realise that they have only ever tasted what they are now able to identify as rancid oils. I always explain that I first smell any extra virgin olive oil I buy or that I’m offered to taste, just as you might an oyster to make sure it’s not off before you slip it into your mouth. I cannot imagine, once you have smelled and tasted a good extra virgin olive oil, that you would ever use a rancid olive oil again.

Virgin olive oil

This is simply olive oil that didn’t quite make the grade of extra virgin. Its free fatty acid measurement sits between 0.8 and 3 per cent, and it should be used soon after it is crushed. It will have less flavour and a much shorter shelf-life than extra virgin olive oil. In Europe, a little virgin olive oil is combined with ‘pure’ or refined olive oil to add some flavour.

Olive oil

Still often referred to as ‘pure’ olive oil, it is almost at the bottom of the range in terms of quality, so this is really a misnomer. This olive oil is the result of industrial processing, deemed necessary because the oil has not met the above criteria for virgin or extra virgin olive oil. In this process, the olive oil is refined, using a chemical treatment in which peroxides and free fatty acids are removed to make it suitable for consumption. The oil may also be bleached and deodorised to remove any ‘off’ flavours but, at the same time, this removes many of the natural flavours and antioxidants that are characteristic of extra virgin olive oil. ‘Pure’ olive oil may be suitable for cooking where a less dominant flavour is required, as it still contains some of the fatty acids that make olive oil nutritionally attractive.

Pomace oil

Pomace is the residue or olive waste left after the extra virgin olive oil has been mechanically removed from the olive paste. This solid waste product may contain 3–8 per cent oil, which is called pomace oil. The oil is recovered by washing the waste with an organic solvent such as hexane. The recovered oil is then heated to remove the solvent and the oil is subjected to the same refining processes described for olive oil. As with olive oil, bleaching and deodorising removes not just the unwanted odours but also the fruity characteristics of the olive. It strips any flavour, good or bad, out of the oil, and the resultant oil is fatty in the mouth and tastes of the industrial processes it has been subjected to, even though a small amount of virgin olive oil is generally added for flavour. I have no use for this oil, even for a marinade.

Light olive oil

Light olive oil is a marketing term aimed at the weight-conscious. The only thing light about this oil is that it is light in character – or, to my mind, totally lacking in flavour, colour and aroma. It has exactly the same number of calories or kilojoules as extra virgin and other olive oils but, as it is refined, it lacks the health-giving antioxidants and polyphenols of extra virgin olive oil, as well as the flavour.

Choosing and using extra virgin olive oil

Extra virgin olive oil is never more vibrant than when first crushed. Unlike wine, it diminishes with age – although, as mentioned above, the earlier harvest extra virgin olive oils have a longer shelf-life. As a rule of thumb, only buy an extra virgin olive oil if it displays its year of harvest and you are buying within that year. This doesn’t automatically mean the oil is no good if it’s over a year from its harvest date, but it does mean that unless it has been picked early enough and has enough of that assertive character at the beginning, it will begin to lose its freshness and vitality after a year, and will become ‘flat’ and more prone to rancidity as it gets even older.

I keep two grades of extra virgin olive oil. The first is my own estate-bottled oil which comes from my own trees or those of other producers I respect – and there are many of those in Australia, I am delighted to say. This is the oil that makes all the difference to a dish when added as a last flourish; my own preference is for a robust, fruity oil for the majority of my food where the olive oil flavour dominates. I also use a less expensive Australian extra virgin olive oil from the supermarket that declares its year of harvest and, even though it is cheaper, it is still fresh and fruity. This is the oil I use when serving more delicate dishes (such as poached fish) or for cooking with, as high temperatures dissipate the flavour of extra virgin olive oil to some extent.

In summary, buy the finest extra virgin olive oil you can afford, and use it generously rather than keeping it for ‘best’. I love to have a good extra virgin olive oil on the table at every meal, and either use it in a vinaigrette or simply drizzle it over piping hot vegetables to serve with grilled bruschetta. I also love to use it for dressing sliced raw tuna, moistening goat’s cheese and lavishing over sliced tomatoes. With really good extra virgin olive oil you can turn a simple pasta, such as Spaghettini with Parmigiano Reggiano, Garlic, Capers and Flat-leaf Parsley (see page 40), into a spectacular dish. It is amazing how a splash of extra virgin olive oil over a hot bowl of soup or fresh cannellini beans adds a truly powerful dimension that lifts the flavour to another level.

I use my more mellow everyday extra virgin olive oil for sweating onions, coating foods for a marinade or grilling fish, chicken or meat. If I deep-fry (or probably more often, shallow-fry), once again I use this more mellow extra virgin olive oil. Even though it may sound extravagant, it imparts so much more crispness and flavour, as food fried in extra virgin olive oil gains a wonderfully crunchy coating that acts as a seal and prevents excess oil from penetrating further.

Storing extra virgin olive oil

It is very important to store oil properly to maintain its quality. It should be kept away from light – ideally in dark glass bottles, tins or bag-in-the-box ‘bladders’ to protect it from light, heat and oxygen. Whatever you do, don’t sit the bottle by the heat of the stove or on your windowsill, no matter how jewel-like it may look in the sunshine!

Most importantly, once you open a bottle of extra virgin olive oil, never leave it without a stopper, as exposure to oxygen leads to rancidity. Better still, rather than save it for special occasions, use it frequently – even the smallest amount added to a dish can make such a difference to its flavour.

While I refrigerate my nut oils to control their rancidity, I never refrigerate my extra virgin olive oils as it changes their structure. Although this reverts to a certain extent if the oil is returned to room temperature, I find there is a loss of flavour and ‘texture’– a funny word perhaps when talking of oil, but a relevant one nonetheless.

Words: An extract from the book Maggie Beer’s Winter Harvest Recipes by Maggie Beer (Lantern, $29,99) // Photo: Mark Chew

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