About Olive Oil
Olive oil is a greenish, yellowish, liquid oil obtained in its natural state without any chemical process, without any additives, by being squeezed directly from the fruit of the olive tree and can be consumed as a liquid at room temperature. Its difference from vegetable oils such as sunflower, soybean, cotton seed and corn oil is that it is produced naturally.
As the olive oil is obtained from pressing the flesh of the olives as well as their pits, it is technically a “juice” contrary to other edible oils obtained from seeds. It is raw and pure, like freshly squeezed orange or cherry juice. Olive oil does not have a fixed composition. Because olive oil varies according to the type of olives used, the year of production, the region where the olive comes from and the method of pressing the olive. It also differs from year to year. Olive oil is a complex composition of oleic acids, vitamins, volatile ingredients, water-soluble ingredients and microscopic olive particles.
World olive oil production is around 2.91 million tons per year according to the average of the last five seasons. Important olive oil producing countries are, Spain, Italy, Greece, Turkey, Tunisia and Morocco respectively (Uzka, 2018).
Turkey has a total number of 182076 olive trees. 154037 of them are fruit bearing trees whereas 28039 don’t bear fruit (TurkStat, 2019). Of the total olive production of 1525000 tons, 415000 tons are used as table olives and 1110000 tons for oil production (TÜİK,2019).
Olive Oil Type (Communiqué No: 2017/26)
a) Natural Olive Oil: Obtained by applying only mechanical or physical processes such as washing, decantation, centrifuge and filtration processes in a thermal environment that will not cause any change in their natural qualities from olive tree fruit; Refers to the oils that have the physical, chemical and sensory properties of the products in its category. Oils obtained by use of solvents or additives with chemical or biochemical effects or by re-esterification are excluded from this definition.
Natural Olive Oils are classified as follows;
1) Extra virgin olive oil: These are the olive oils suitable for direct consumption with the free oleic acidity in terms of oleic acid is not more than 0.8 grams per 100 grams,
2) Virgin olive oil: These are the olive oils suitable for direct consumption with the free oleic acidity in terms of oleic acid is not more than 2.0 grams per 100 grams,
3) Crude / Refining Olive Oil: It is the olive oil with the free oleic acidity in terms of oleic acid is more than 2.0 grams per 100 grams or which is not suitable for direct consumption in terms of its sensory and characteristic properties, suitable for refining or technical use.
b) Refined olive oil: It is the oil obtained by refining the raw olive oil by methods that do not cause any change in the natural triglyceride structure and has free oleic acidity in terms of oleic acid not more than 2.0 grams per 100 grams.
c) Riviera Olive Oil: Riviera oils are obtained by a mixture of virgin olive oil and refined olive oil and are suitable for direct consumption. The Riviera olive oils’ free oleic acid ratio in form of oleic acid does not exceed 1.0 g per 100g.
d) flavored olive oils: It is an oil obtained by adding different spices, herbs, fruits and vegetables to olive oil and bearing the characteristics of the products in its category within the scope of the Turkish Food Codex Olive Oil and Pomace Communiqué.
Production of Olive Oil
1. Receipt of Olives: Olives should be harvested in the ideal maturity period, by hand or by machine, without touching the soil, so as not to damage the fruit. The quality of olives collected from the ground is lower than the quality of olives collected from trees. Microbial or enzymatic degradation resulting from fruit damage during harvest also causes low quality oil. After harvest, the olives should be brought to the press in plastic boxes suitable for food transport ensuring ventilation as soon as possible. Quality problems occur in olive oils obtained from olives brought to the press in sacks or airtight containers.
Throughout the process, the olives of different qualities must be sorted and separated. For instance, the low-quality olives like bottom olives, fermented olives, molded olives, etc. must be stored and pressed separately. In addition, if different quality products are processed consecutively in the system, additional measures should be taken such as processing higher quality olives first or cleaning the system after processing lower quality olives. It is recommended to process all olives within twenty-four hours after they are received in the press. However, under no circumstances, the processing time should not exceed three days.
2. Leaf Separation and Washing: The olives received and accepted in the press, must be cleansed from rocks, soil and foreign matters and must be washed. Foreign substances reduce the quality of the oil and affect the sensory properties such as taste and smell.
The purpose of leaf separation and washing is to ensure the removal of foreign substances as well as to prevent these foreign substances from damaging the decanter (tool and equipment) during processing. Leaves, twigs, other plant materials and mineral materials such as soil, dust, pebbles and stones are separated from the fruits by vibration, air flow or sieving.
In addition, during the washing of olives, soil, mud and stone pieces are separated by the circulation of pressurized water. The water used for washing should be potable, the pollution of the water should be controlled, and water should be replaced at appropriate frequency according to the workflow intensity.
3. Crushing: The olives, which are purified from foreign substances and washed, are subjected to crushing to extract the oil droplets in their cells. Stone or metal mills (crushers) are used for this process. While stone mills are generally used in classical systems, metal crushers are preferred in continuous systems.
4. Malaxation: After the olive is crushed, they are mixed. Especially when metal mills are used, mixing is an important step in the preparation of the paste for the subsequent separation of solid-liquid phases. The mixing process has an important function in combining the oil drops to facilitate the solid-liquid separation. "mixing" or "malaxation" enables small oil droplets to merge with each other to turn into larger droplets and leak. The temperature of the olive paste should be around 25-35 oC in order to reduce the viscosity of the oil and to allow the oil drops to combine easily. However, this temperature may be lower depending on the type or the characteristics of the olive, for example, it should be maximum 27 oC for cold pressing. In order to obtain quality oil, it is recommended to have the temperature of the malaxer around 30 oC and the mixing period should not exceed one hour. However, it can also be heated up to 60 OC to get more oil from the paste. This is called "hot pressing". Long-term and high temperature mixing increases oil yield. Bu it also causes oxidation, loss of polyphenols and a decrease in the positive sensory properties of olive oil. Mixing temperatures higher than 50-60 oC increase the solubility of waxes, aliphatic alcohols and triterpene di-alcohols in oil, resulting in non-standard olive oil production. These values are the properties that distinguish virgin olive oil from olive pomace and refined oil. Two critical parameters of consideration during the mixing process are the mixing time and paste temperature.
5. Solid-Liquid Phase Separation: This process is performed in different ways depending on the production technology.
a) Hydraulic pressing (wet press): In this process, the oil and the wastewater (black water) is separated from the solid phase by application of hydraulic pressure on the olive paste which is manually or mechanically distributed in the press bags. In that stage, oxidative products may occur, natural antioxidants may migrate to liquid phase or organic residues and impurities may migrate to olive oil phase and the sensory properties may change. Minimum amount of water should be used in hydraulic pressing and the temperature of the water should not exceed 30 oC. Attention should be paid to the pressing pressure and the cleanliness of the press bags used.
b) Sinolea / Percolation / Cold Dripping / Selective Filtration: By dipping the plates made of stainless steel into the olive paste in the malaxer, phases are separated by means of surface tension between the liquid phases (oil and wastewater). In Sinolea method, 25% of the oil is taken and the remaining olive paste is processed in a continuous centrifuge system. The rotation speed of the plates within the olive paste is important.
c) Continuous Centrifuge Systems: In decanters, solid and liquid phases are separated by horizontal centrifuge based on the density differences. This process is divided into two categories in decanters: double phase and triple phase. In triple-phase decanters, oil, pomace and wastewater are separated at the output of the system. In double-phase decanters, oil is separated from pomace and wastewater as outputs. The amount of water added during the decantation phase, effective cleaning of the decanter and the correct selection of the rotation speed are important factors. The amount of water added in the decanter is approximately 15-20% of the weight of olives for triple-phase decanters and approximately 10% for double-phase decanters.
6. Liquid-Liquid Phase Separation: Although it varies according to the production technology, in the traditional system based on density difference, liquid-liquid phase separation is made by using natural settling or centrifuge. At this stage, it is aimed to completely separate oil, water and pulp. In double phase or triple phase systems, phases are separated by use of centrifuge. If the phase separation process is performed under undesirable conditions such as the rotation speed of the centrifuge, the amount and temperature of the washing water used, the contact time of oil and water, unfavorable color, taste and odor can occur.
7. Pre-Storage of Olive Oil: Oils produced in batches are rest after the centrifuge before being classified according to their physical, chemical and sensory properties.
8. Storage of Olive Oil: Olive oil storages should be separated from the production environment. Materials suitable for contact with food should be used in the storage of olive oil. It is recommended to store the oil in stainless steel or chrome nickel coated tanks by preventing the contact of the oil with air as much as possible with inert gas or floating cover systems in order to prevent loss of quality values of especially extra virgin and virgin olive oils. Tanks should be designed with a conical bottom, easy to clean, generally level controlled and suitable for sampling. Since factors such as olive oil's long-term contact with air, increase in ambient temperature, exposure of the oil to intense light, penetration of foreign and unwanted odors and chemical migration can cause oxidation and deterioration of the oil, it is important to control the storage conditions, to perform periodic cleaning and to keep the tank lids closed all the time. It is important that the tanks are full in long term storage. It is recommended to store olive oil at a maximum ambient temperature of 22 oC.
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OLIVE
SEPERATION OF LEAVES AND WASHING
CRUSHING
MIXING (MALAXATION)
CLASSICAL SYSTEM MODERN SYSTEM
PRESS Double Phase Triple Phase
Pomace Oil + Wastewater Centrifuge Centrifuge
Centrifuge Pomace Oil + Wastewater
Pomace Oil + Wastewater
Pomace Oil Wastewater
Proper packaging allows storage of the products delivered by the producer to the distant consumers without losing quality due to external factors as well as promotion of the product. Tin, glass, plastic (PVC, PE, PP) and specially coated cardboard boxes are used as packaging materials. The main factors for an ideal packaging can be listed as follows;
One of the most important aspects of packaging is deciding which values will be highlighted for olive oil types as well as usage patterns and the mode in which these values will be reflected. The label is a kind of the promotion card of the product and it directs the consumer to use the product in the most correct way. The information on the label must be in accordance with the TFC Food Labeling and Consumer Information Regulation.
Packaged products should be stored in cool places out of direct sunlight. Olive oil absorbs
all odors. For this reason, it should be kept closed in places which does not contain any odor.
Two factors are important for the quality of a natural olive oil. First is the acidity which can be measured by chemical analyses. Second, the detection and measurement of the taste and smell. The color of the olive oil shall not be considered a quality indicator. The color varies according to the variety of the olives, their maturity and harvesting period. Only smelling and tasting would provide information about the sensory qualities of the olive oil.
The physical and chemical properties of olive oil vary depending on many factors such as olive type, climate and soil conditions, the maturity of the olives used, and the methods used in olive oil production.
CRITICAL CONTROL POINTS FOR QUALITY PRODUCTION
For the olive oils, quality starts with harvesting of the olives and continues during pressing and bottling.
When stored in appropriate storage conditions, in a dry, cool place devoid of foreign odors and out of direct sunlight in colored glass bottles, larger glass containers or lacquered tin containers in an air-tight way, the natural olive oils preserve their qualities for 24 months and refined olive oils preserve their qualities for 18 months.
QUALITY PARAMETERS
PURITY PARAMETERS
PARAMETER STANDARDS AND NORMS
TS 341 Edible Olive Oil Standard
Olive Oil and Pomace Communiqué 2010/35 of Turkish Food Codex
International Standards and Norms (ISO, AOCS)
International Olive Oil Council Commercial Standard (IOCC)
European Union Norms (EEC)
Codex Alimentarius
The most olive oil consuming countries of the world are, respectively, Spain, Italy, USA, Turkey, Morocco and Greece (IOC, 2018). Annual per capita olive oil consumption is 12.8 kg in Greece, 11.3 kg in Spain, 10.5 kg in Italy and 7.2 kg in Portugal. Despite a significant increase in recent years, per capita annual olive oil consumption in Turkey is limited to mere 1.4 kg. Considering the per capita consumption is above 3 kg even in Lebanon, Jordan and Tunisia, Turkish consumption rates appear rather low. In the USA, which is not a member of the International Olive Council, consumption per capita is 0.9 kg, but has been increasing rapidly in recent years (UZK, 2018).
There are many ingredients that give olive oil its unique flavor. Phenolic compounds are among these. Phenolic compounds play an important role in preventing free radicals.
Olive oil is a rich source of antioxidant Oleuropein and Hydroxytyrosol. Hydroxytyrosol is a natural-strong phenolic antioxidant found in olives and olive oil and is the major breakdown product of oleuropein. Hydroxytyrosol is the most powerful natural free radical suppressor. It gives the olive oil its aroma and prevents it from getting bitter. It is found in processed olives and olive oil. Fresh olive oil contains it in lesser amounts. In olive oil production, at the end of the processing of olives, the amount of oleuropein decreases over time, while the amount of hydroxytyrosol increases.
Oleic acids are processed in human body and turn into fatty acids according to various properties. There are exceptions though. Oleic, linoleic and linolenic acids must be supplied from outside as they are. The human and animal body cannot produce them by processing other fatty acids. However, these have very important functions for the organism. These fatty acids are called essential fatty acids. Because they are essential for health. The two most important essential fatty acids are Omega-3 (alpha-linolenic acid) and Omega-6 (linoleic acid) fatty acids. Excessive Omega-6 and very little Omega-3 fatty acids are taken with the usual modern diet. Olive oil does not change the ratio of Omega-6 to Omega-3 in the human body. It is very important to supply Omega-3 and Omega-6 into the body at certain volumes. Because deterioration of these rates can result in deterioration of many diseases, including heart, immune system diseases and cancer.
Olive oil contains α-tocopherol, which shows the highest vitamin E activity. Olive oil contains vitamin E and polyphenols (antioxidant). Each 10 grams of olive oil contains 5 mg of polyphenols. The richest sources of vitamin K are green leafy vegetables. Vegetable oils such as olive oil are the second most important source. Olive oil contains Vitamin A, Vitamin D and trace amount of phytosterol. Moreover, the calcium, phosphor, potassium, sulfur, magnesium, iron, copper, mineral contents of the olive oil play an essential role in bone development.
Cardiovascular diseases are the leading causes of death in the modern industrial world. Studies on the causes of these diseases show that dietary habits and lifestyle affects their occurrence to a large extent. Studies show that a diet rich in olive oil significantly reduces the occurrence of heart diseases. With the oxidation that occurs in human body, harmful radicals are formed, and their harmful effects can only be eliminated by antioxidants. Therefore, a diet rich in olive oil enhances resistance of cells against oxidation. This means that the olive oil is an anti-ager product.
Carotenoids and phenolic compounds and the vitamin E are of great importance in preventing cancer and other major diseases as well as delaying aging. Olive oil is a foodstuff very rich in these compounds. These antioxidants are compounds found only in fresh vegetables and fruits, and for this reason, olive oil is distinctly different from other oils in terms of antioxidant content, since it is an oil obtained directly from fruit by mechanical methods.
Thanks to the antioxidant compounds contained, the olive oil is an important aid in fighting cancer diseases, which develop as a result of cell oxidation. Regular consumption of olive oil has been shown to prevent high blood pressure. Studies show that diets rich in olive oil, low in saturated fat and moderate in carbohydrate and fiber-rich vegetables and fruits has plenty benefits against diabetes disease.
Olive oil is a food that has perfect biological values. Naturally it has a high caloric value (9 kcal/1 g) just like any other oil. But the experience shows that the societies on Mediterranean diet, which is an olive oil-rich diet, obesity is a less frequent health problem.
The benefits of phenolic components, antioxidants, vitamins and unsaturated oleic acids in olive and olive oil can be listed as follows:
Table olives raised by members of the cooperatives in Gemlik, Mudanya, Erdek, Orhangazi, Iznik, Edincik, Murefte and Marmara Island which are affiliated branches of our Union, are sorted according to their size and the smaller sized olives are brought, without delay, to the continuous integrated system facilities of the Union which boasts as daily olive processing capacity of 220 tons.
Olives are firstly washed and separated from foreign matters like leaf with the help of powerful aspirators. The cleansed olives are crushed together with their seeds by hammer mills to obtain olive paste. The paste obtained is mixed in a malaxer and heated to a maximum of 30- 35 oC.
Olive oil output is stored in stainless tanks. After resting for a certain period of time, it is passed through special filters and then automatically packaged.
The olive oils produced in our facilities are put into market in various packaging:
The olive oils produced in our facilities are classified based on the method of production as follows: