The olive tree has a great lifespan and retains its productivity for centuries. For example, in the Peloponnesus as well as in Crete and Paxi, there are olive trees that are at least 1000 years old. The olive tree does not bear fruit for the first six years of its life.

The olive tree has a great lifespan and retains its productivity for centuries. For example, in the Peloponnesus as well as in Crete and Paxi, there are olive trees that are at least 1000 years old. The olive tree does not bear fruit for the first six years of its life.

WHAT IS OLIVE OIL?

Olive oil is the natural juice that is produced from the olive tree fruit by physical means (crushing, pressure, centrifugation, sinolea), without the addition of chemical refinements or further processes. That is why it can be immediately consumed, like all natural juices.

WHICH ARE THE OBJECTIVE CRITERIA OF GOOD OLIVE OIL?

The International Olive Oil Council (IOOC) evaluates olive oil based on three main factors: acidity, oxidization and organoleptic features (i.e. smell, colour, taste).

Acidity: Acidity is the most important criterion for professionals and consumers. It determines the quality classification, the gradation, and the price. The fatty acids of the oil are either free or bound with glycerol. Free fatty acids form the acidity. The given acidity is usually indicated by a percentage: the greater the percentage, the more free fatty acids in the oil. The degree of growth results from several factors that influence the fruit from a very early stage. For example, dakos is a specific disease affecting olive trees, hurting the fruit during gathering, storage, and final crushing.

Oxidization: Oxidation occurs when olive oil becomes rancid. This results from exposure to unsuitable conditions after its extraction from the oil press. Oxidization is defined by laboratory measurements, including the number of hyperoxides.

Colour: The colour range of olive oil usually varies from dark or light green to dark or light yellow. The colour is determined by the prevalent colouring substances of the fruit at the time of the gathering. For green olive oil, the fruit was gathered at an early stage, when it was still unripe or semi-ripe; this oil is usually bitter. Olive oil may also have a vivid green colour if leaves or small twigs are included when grinding. For an unripe or slightly ripe fruit, a purple-blue chlorophyll results. Yellow olive oil was gathered when the fruit was fully ripe and still on the tree; a vivid yellow oil may also indicate oxidization. When the colour is dark brown or black, then the oil comes from fruit that has fallen on the ground. These kinds of oil have a milder, sweeter taste. The system of crushing the olive crop and extracting the oil also plays an important part in the determining the colour.


WHAT QUALITIES OF OLIVE OIL ARE THERE?

The quality grade of olive oil is chiefly based on commercial criteria established by the International Olive Oil Council. The major quality criteria are acidity, oxidization and organoleptic features. Many consumers find it difficult to evaluate quality olive oil, because the public is not informed of the differences in quality and taste among the various categories of olive oil on the European market.

Consumers do not always have the financial means to buy brand name olive oil. Even in Greece, only 30 percent of consumption comprises standardized brand name olive oil; the remaining 70 percent is unstandardized or unbottled. However, this doesn’t mean that olive oil from small-scale growers is always of low quality. Thus, we must first sort out the quality grades that are on the market.

A. VIRGIN OLIVE OIL

Virgin olive oil is taken exclusively from the olive tree fruit by physical or mechanical means, which don’t cause alterations in its final quality. Virgin olive oil is a natural fruit juice that contains all the nutritious elements that are beneficial to health. This oil has not undergone any process apart from crushing, decanting, centrifuging or filtering. Depending on its degree of acidity, as well as its taste characteristics, virgin olive oil is divided into the following categories:

Extra virgin olive oil has an acidity of 1g per 100g of oil or 1 percent and is considered the highest quality. It is taken from the olive crop exclusively by mechanical or physical means and always under low temperature conditions.

Fine virgin olive oil is often labelled “choice” or “fancy” and has an acidity of less than 150, according to the IOOC. On the other hand, according to EEC regulations, the acidity level may rise to 2 grams per 100 grams of olive oil.

Semi-fine virgin olive oil has an acidity of 3 grams per 100 grams of olive oil.

Lampante virgin olive oil has high acidity, resulting in poor taste, smell, and colour. It is impossible to consume, as it must undergo chemical processes and refinement.

B. REFINED OLIVE OIL

Refined olive oil is chemically treated and comes from the industrial lampante. This limpid olive oil is usually light yellow and free from high acidity (3 to 5). Generally, it is neutral with no distinctive flavour or aroma and also lacks the beneficial elements of virgin olive oil.

C. OLIVE OIL

Olive oil is a blend of high quality virgin olive oil and refined olive oil. The mixing analogies vary and depend on the demands and commercial policy of the companies. Nevertheless, the final product must taste and smell pleasant, be a light yellowish green colour, and have an acidity between 1 and 5.

DOES OLIVE OIL MAKE FOR BETTER HEALTH?

Natural olive juice: the elixir of health and longevity
For centuries, the natural juice of olives, which has an ideal chemical structure and no extracts or refinements, has provided health and longevity for the Mediterranean people. Its alimentary, nutritional, and biological value is important; olive oil is among the 10 most beneficial foodstuffs. The following table presents its constituent substances, to which 600 antioxidizing substances should be added.

Vitamin E 3 – 30mg
Provitamin A ( CAROTENE )
Monounsaturated fatty acids 56-63% (Oleic acid)
Polyunsaturated non fatty acids 3,5 – 20% (Linolenic acid)
Polyunsaturated fatty acids 0 – 1,5% (Linolenic acid)
Saturated fatty acids 8 – 23,5%
Lipids 99% ( 990cals/100g)

Olive oil (like all oils) contains fatty acids, which may be saturated, monounsaturated, or polyunsaturated. Animal fats mainly contain saturated fatty acids; seed oils contain polyunsaturated mainly fatty acids. Olive oil contains mostly monounsaturated fatty acids (up to 83 percent in the form of oleic acid), few saturated fats, and basic polyunsaturated fats such as linoleic acid. The coexistence of the oleic acid with the linoleic and linoleic acids gives olive oil its unique biological value.

Natural antioxidizers: In addition to fatty acids, olive oil contains small quantities of other elements with beneficial properties, such as vitamins A and E, minerals, selenium, and a heterogeneous class of polyphenolic substances called antioxidizers. These antioxidizing substances protect cells from oxidative stress, active oxygen, and free radicals. Free radicals substances that can damage nucleic acids and proteins; they are considered factors in chronic diseases such as cancer. The present survey deals with the role of these microelements as protective factors against chronic diseases, with a particular emphasis on cancer.

Olive oil and digestion: Compared to other fatty substances, olive oil is the most tolerable for the human stomach. Olive oil can reduce gastric fluids, diminishing the feeling of indigestion. Moreover, it creates a feeling of satiety and aids in digestion. In one study, patients with ulcers who ate food prepared exclusively with olive oil reported reduced pain.

Clinical research shows that olive oil has a high absorption capacity from the mucous membrane of the intestine. It alleviates many intestinal syndromes and supports the functioning of the large intestine while reducing symptoms of constipation. One or two spoonfuls of uncooked olive oil early in the morning are ideal for people who suffer from chronic constipation, or those who are pregnant, fasting, and or eating diet with a high proportion of protein.

Olive oil and bile: According to Chinary (1932), Touarte was the first doctor to officially recommend olive oil as treatment for cholelithiasis and hepatic colics in 1887. According to Chinary, olive oil is not capable of destroying or dissolving stones, but it promotes the excretion of bile. It is recommended that patients who suffer from bile, dyspepsia, or stomachaches take 1 to 2 spoonfuls of pure virgin olive oil flavoured with a few lemon drops each morning for 10 days a month.

Olive oil and skin: Olive oil protects the skin from solar radiation due to the concentration of vitamins E and A as well as to its polyunsaturated fatty substances. Moreover, it suspends the development of children’s eczema and relieves insect bites. Research also shows that chlorophyll, found exclusively in olive oil, promotes metabolism, stimulates the growth of cells, and contributes to blood production, thus precipitating wound healing.

Olive oil and age: Aging is a progressive process that comes with a series of biological changes that inevitably lead to death. Research in the past decade suggests that those who consume olive oil are protected from changes in the central nervous system and the brain, thanks to its antioxidizing properties.

Olive oil and cancer: According to Dr. Trihopoulos of the Harvard School of Public Health, women who consume olive oil more than once daily reduce their risk of developing breast cancer by 25 percent. In the Mediterranean region, where olive oil consumption is high, there are lower rates of breast, ovarian, and endometrial cancer.

Olive oil, cholesterol, and the heart: Over the last decade, epidemiologic studies (Seven Countries Study) concluded that olive oil protects the body from cardiovascular problems. The Mediterranean diet, especially for Cretans, includes plenty of fruits, vegetables, fish, and olive oil. Although red wine, the environment, and cultural beliefs might also play a role, the main source of protection appears to be olive oil. The prime cause of cardiovascular disease is not the total quantity of fat but the type of fat that a person consumers. The right combination of saturated and monounsaturated fats protects the heart.

Scientific interest in olive oil was rekindled by the realization that a high concentration of “good” cholesterol (HDL) is as important as a low concentration of “bad” cholesterol (LDL). Olive oil increases HDL and decreases LDL, thus building a very balanced lipid system in the blood and restricting the formation of fatty plaque along the artery walls, which develops into thrombus and can cause coronary heart diseases and myocardial infarctions.

In his study, Antonis Kafatos, Professor of Preventative Medicine and Nutrition in the University of Crete, found that men from Crete had the greatest ability to deal with fatty substances after a meal because of their olive oil consumption, which restricts the formation of thrombus, minimizing heart attack danger.

Olive oil and childhood development: Adequate nutrition is especially important for infants and children. Lipid demands are greater in childhood. According to a rough estimate, breastfed children receive 50 percent of their total calories in the form of lipids, with a ratio of saturated to monounsaturated and polyunsaturated acids of 4:3:1 and with average cholesterol of 150 mg. Polyunsaturated fats comprise 8 to 10 percent of these lipids; 5 to 8 percent belong to the ω3 series. The amount of lipids received later reduces to 30 percent in the later childhood years, until it adjusts to relative adult demands.

Infants should received fats in ratio of 4:3:1 for saturated, monounsaturated, and polyunsaturated fats, which is proportional to that of human milk. An experimental study concerning olive oil, sunflower oil, and saturated fats reports changes in the structural lipids of the brain and the liver of animals that are exclusively fed with sunflower oil. These changes prove that developing tissues demand an adequate quantity of basic fatty acids. Olive oil provides the fatty acids needed for the growth of newborns and has a glycerol composition that is similar to mother’s milk.

According to new studies, olive oil also benefits the growth and development of the central nervous system. Its monounsaturated oleic acid and linolenic acids can prevent high cholesterol levels. Furthermore, mothers who breastfeed and have large quantities of olive oil in their daily nutrition produce milk with excellent fatty acid content.

Olive oil and skeletal growth: In 1980, Laval-Jeantet and his colleagues conducted a study on the role of lipids in the development of the human skeletal system. In this study, recently weaned mice were given foods whose lipids differed in terms of quantity and fatty acid composition. They found that lipids are of vital importance to the development of the skeleton: “the best development and the addition of mineral elements are observed in the case of taking oleic glycerids, which are complemented by the smallest quantity of polyunsaturated fatty acids, which mainly exist in olive oil.”
The same researchers discovered differences in bone size, breadth, and texture in people who consumed olive oil, concluding that oleic acid plays a major part in the development of bone tissue.

Olive oil and athletics: Lipids and carbohydrates provide energy for physical activity. During rest and moderate activity, lipids form the main energy substratum; during intense activity, the carbohydrate contribution decreases. During lasting intense activity, lipid consumption gradually increases. Thus, athletes should consume a diet that is rich in fats. As far as energy output is concerned, no substantial differences have been found among the various fatty acids. However, some researchers claim that unsaturated fatty acids are better than saturated fats. Athletes should restrict their intake of animal fat, because the presence of saturated fatty acids combined with the existence of high cholesterol levels can lead to ischemic cardiopathy. The effects of lipid peroxidization and the reactions of the free radicals shouldn’t be underestimated, because they can even cause damage to the skeletal and cardiac muscles of athletes.

Athletes can restrict free radical development through a diet rich in fresh fruit and vegetables and monounsaturated fatty acids (olive oil). Lipids should comprise at least 30 percent of their total calories. Monounsaturated fatty acids are preferred, since they are not sensitive to peroxidization processes and do not create free radicals. Olive oil is preferred for its natural antioxidizing properties.

Olive oil and diabetes: Olive oil plays an active role in keeping sugar levels low for insulin-independent diabetes patients. Consuming 30 to 45 percent of olive oil decrease lipoproteins A and B and triglyceride levels in the blood serum. Sintori (1986) claims that olive oil can slow down the emptying of the stomach’s content into the duodenum, so that carbohydrate digestion does not lead to sudden increases of glucose in the blood. Thus, olive oil leads to stable glucose levels and the inactivation of the liver neoglucogenesis mechanism.

DO ALL OLIVE OILS TASTE THE SAME?

Two basic organoleptic features, aroma and flavour, are the most important criteria for evaluating olive oil. Organoleptic control is achieved by specialized tasters according to the rules and standards determined by the International Olive Oil Council. Thirty minutes prior to tasting, these people are forbidden to smoke or use any perfume, deodorant, or even soap substances that may affect their final judgment. An hour before tasting, it is also forbidden to taste any food, and they cannot participate in the tasting process if they are taking any medication, have a cold, or are under psychological stress.

AROMA: Like wine, olive oil has a significant number of flavour and aromatic constituents. The natural aroma and flavour depends on the quality of the oil as well as the olive tree variety, the climatic and terrain conditions under which it grew, and the ripeness of the fruit. The greatest concentration of olive oil aromatic constituents is achieved during the period when the fruit changes from vivid green to slightly violet, heading towards black. Some of the aromatic constituents include aldeydes, carbohydrates, and aliphatic alcohols.

Flavours and aromas

Amending regulation 2568/91 of the EEC applies to all olive oil producing countries. This regulation helps us learn the wealth of flavours and aromas the different types of olive oil present.

• Olive ripeness: the smell and flavour of healthy and fresh olives, which have been gathered at the ripening stage
• Ripe: taste of olive oil produced from ripe olives, mostly without smell and with sugary flavour
• Unripe: taste of olive oil produced from unripe olives
  
  

Gutierrez (1977) defines the following substances in olive oil that give it a special aroma and flavour:

APPLE: flavour that reminds one of apples

SWEET FLAVOUR: pleasant, not sugary

GRASS: reminds one of the smell of freshly cut grass

GREEN LEAVES: bitter flavour resulting from unripe olives ground with leaves and twigs

BITTERNESS: flavour produced from unripe olives or olives that have just started ripening; may probably be pleasant according to how intensely perceptible it is

ACRIDNESS: distinct sensation produced by certain olive oils that leaves a slightly acrid taste in the mouth

PUNGENCY: taste sensation of olive oils produced in the beginning of the producing season from mainly unripe olives; results from phenolic substances on the trigeminal nerve, which expand in the oral cavity

ALMOND: fresh or dried almond taste; can also indicate rancidity; results from sweet olives characterized by faint smell

FLAT or FAINT (musty): creates a faint impression; musty aromatic constituents

HAY: distinctive smell of certain olive oils that reminds one of grass
LEMON: flavour that characterizes few olive oils and gives the mouth the sour sharpness of citrus fruits

SORREL: a faint sour flavour of olive oils cultivated near lemon and orange orchards

PEPPER: distinctive piquant flavour of certain olive oils; sharp aroma

Unpleasant flavours and aromas

Oils with these characteristics are considered of low or poor quality:

RUSH: distinctive flavour produced from olives stacked in new bags made of fresh or dry rush

EARTH: distinctive flavour produced from olives gathered with earth or mud; may be combined with mould

MOULDY: distinctive flavour of olive oil kept too long in storage containers

WORM: distinctive flavour produced from olives severely affected by the chrysalides of “dakos”

METAL: distinctive flavour of olive oil that has been in contact with metallic surfaces for a long time

MILDEW: distinctive flavour of produced from olives that have become mouldy after prolonged exposure to dampness

RANCID: unpleasant flavour that indicates oxidization

MUSTY SMELL: distinctive flavour produced from advanced fermentation

BRINE: distinctive flavour produced from olives preserved in salt solutions

CUCUMBER: flavour that results from prolonged airtight storage, mainly in tin containers, or oils overheated during production

COOKED or BURNED: distinctive flavour of olive oils that have been overheated during crushing

DREGGISH: flavour resulting from storage in containers that have not been cleaned well after previous use

LUBRICANTS: unpleasant smell resulting from inadequate cleaning of extracting equipment

WALNUTS: unpleasant smell that reminds one of stale dried fruit

HOW DO I TASTE OLIVE OIL?
Tasting is a complex procedure. People who are not used to tasting cannot retain the flavour and aromatic characteristics of more than 4 or 5 olive oils at a time. To begin, choose five olive oils of the same type but produced in different European regions. For example:

• Olive oils bottled by small-scale producers or by farmers’ co-operative units
• Olive oils standardized by large-scale known and brand name industries and companies (found on supermarket shelves).
• Unbottled oils from various producers
• Olive oils from a specific region of a country but from different prefectures
• European organic olive oils
  
  

• Type of oil (extra virgin, fine virgin, etc.)
• Acidity degree (note if the oil was produced by the cold-press method or if the cultivation is organic)
• The allowed containers in litres are: 0,10/ 0,25/ 0,50/ 0,75/ 1/ 2/ 3/ 5 and 10.
• Country of origin
• Local origin
• Name and address of the standardizer, bottling unit, producer, seller, importer, or exporter
• Bottling date and expiry date (should not exceed 15 to 18 months)
• Preservation conditions (temperature)

OLIVE OIL AND MEDITERRANEAN COOKING
The cornerstone of Mediterranean cooking is olive oil. It is also consumed in daily diets, cooked or uncooked using various techniques. Good uncooked olive oil allows the flavours and aromas of the rest of the ingredients in the dish to shine. Many claim that it takes more skill to cook a dish made with oil than any other high-class gastronomic and complex preparation.

Uncooked

Extra virgin olive oil has strong organoleptic features, making it is ideal for salads or with vinegar or lemon. Use it with:

• Fresh boiled vegetables, wild greens, boiled or roasted potatoes, peppers, zucchini, cauliflower, broccoli, notchweeds, black nightshades, black mustard, and chicories.
• Complex salads made with potatoes, bread, aubergines, garlic, parsley and fish roe
• Raw or grilled cheese with oregano, savoury, or thyme
• Boiled meat or poultry.
• Rusks, especially barley ones, or on toasted bread
• Marinades for fish and meat
• Aromatic herbs and greens

In the oven

• Olive oil has the ability to keep meat, fish, and vegetables tender in the oven.
• Olive oil mixes well with butter or margarine, especially in foods and desserts that are oven-baked.
• For desserts, oil keeps cakes moist and gives biscuits and cookies a crisp texture.
• Olive oil can be used as a non-stick substance in baking pans.
  

Barbecues and grill

Put the meat, poultry, fish, and vegetables in marinades with aromatic greens, spices, and olive oil. You can also baste the food with oil before barbecuing or grilling. The taste will improve, the food won’t stick to the grid or turn black, and it will achieve a nice brown colour.

Casserole

Traditional Mediterranean cooking has dozens of casserole dishes. The main ingredients are olive oil, vegetables, wild greens, legumes, meat, potatoes, or pasta. Casserole dishes cooked with olive oil demand great attention, due to the relationship between olive oil and water. It’s good to stew them at a low temperature and with the casserole lid open, so that the water evaporates to leave the dish with only the oil.

Frying

Fats oxidize as a result of high temperatures. Olive oil, thanks to its natural abundance of monounsaturated fatty acids, can resist very high and prolonged temperatures before undergoing changes. Varela (1980) studied the kinetics of the olive oil in fried food compared to other fatty substances like seed oils. Potatoes, fish, and bananas were fried in virgin olive oil, refined olive oil, soy oil, a mixture of soy and olive oil, arachid oil, cottonseed oil, margarine, butter, and lard. Foods fried in olive oil formed a thin crust that increased fat content, while all other fatty substances produced a thick crust with less fat. Olive oil created a thinner, crisper crust for a longer time. These results show that olive oil does not penetrate food but remains on the surface, while all other fatty substances fully penetrate it. Moreover, the oleic acid does not change after frying. Therefore, contrary to popular belief, olive oil is good for frying, if used correctly.

Flouring food before frying creates a protective crust that retains moisture and nutrients. Olive oil contains a certain amount of moisture that is released gradually, if the oil remains between 100 and 150C. Fried olive oil remains easy to digest, even after successive uses, although many experts claim that you should not use oil more than 5 or 6 times for frying. However, many studies found that olive oil was absorbed by the stomach and the intestines even when used repeatedly for frying.

Giving 40ml of uncooked or preheated virgin olive oil to volunteers, through the duodenum, researchers discovered there are no differences between uncooked and preheated olive oil regarding their bile properties.

Corn oils overheat at 160C; sunflower oils, at 170C, creating toxic by-products called “total polar materials” (TPM). Unfortunately, TPM may appear in unheated oils due to poor preservation conditions. Olive oil overheats at 200 to 210C. During frying, the creation of peroxides and free radicals, which have a negative influence on the central nervous system function, is noticeably restrained.

Thus, we can conclude that olive oil is the most appropriate fatty substance for frying, since it has the greatest resistance to changes caused by oxidization. We could also claim that the gastronomy of Greece revolves around a huge frying-pan, since frying is one of the oldest methods of cooking in the Mediterranean.

WHERE AND HOW MUCH OLIVE OIL SHOULD I USE?

Extra virgin olive oil is ideal for raw and boiled salads, plain sauces, stewed or grilled fish and meat, bread or barley rusks, garlic paste, tzatziki, and in preparations where it is not necessary to heat the oil.

Fine virgin olive oil is appropriate for baked, grilled, fried, or barbecued dishes. It is also suitable for kneading dough.

Semi-fine virgin olive oil is mainly used for dishes cooked in oil, like casseroles.

Lampante virgin olive oil is impossible to consume as is and must undergo chemical processes and refinement.

Refined olive oil is processed from the industrial lampante olive oil. It has a neutral flavour but gives greasiness needed for pastry recipes, like baklavas, lenten cookies, melomakarona, and kourabiedes. It is more common in urban pastry-making.

Olive oil has a mild flavour and is used for general cooking.

Regarding what amount of olive oil is required for each use, simply replace other cooking fats with the same amount of oil.

IN CONCLUSION WHY OLIVE OIL AND NOT SOME OTHER KIND OF OIL?
The pure natural juice of olives is clearly superior to every other fatty substance, whether this comes from animals (lard, butter) or vegetables (corn oil, soy oil, palm oil, sunflower oil). Its taste, aromatic, nutritional and biological elements make it unique.

• Olive oil, especially extra virgin, is the natural juice that is produced from the olive tree fruit by physical means (crushing, pressing,centrifugation, sinolea), without the addition of chemical refinements or further processes. It can be immediately consumed, like all natural juices.
• Olive oil has important aromatic substances and trace elements that make it the tastiest of all fatty substances.
  
• Its calorie value doesn’t exceed that of any other fatty substances.
• Thanks to its increased content of polyphenols and tocopherols, olive oil has a special resistance to rancidity and oxidization.
• It is ideal for frying food, more than any seed oil, because it is rich in monounsaturated fatty acids and natural antioxidizing substances.
• The chemical composition of olive oil is ideal. Olive oil is enriched with natural antioxidizing substances that are of the utmostimportance for human health, as is shown by the latest medical studies.