Types of Olive Oil
1. 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.
In addition, natural olive oils are divided into two as “suitable for direct consumption” and “not suitable for direct consumption”.
2. Refined Olive Oil
It is an oil with its unique taste and odor, which is obtained by refining the raw olive oil with methods that do not cause any change in the natural triglyceride structure, and in different shades of yellow. Free fatty acidity should not be more than 0.3 grams per 1000 grams in terms of oleic acid.
3. Riviera Olive Oil
It is an oil with a distinctive flavor and smell, consisting of a mixture of refined olive oil and natural olive oils that can be consumed directly as food, varying from green to yellow. Free fatty acidity should not be more than 1.0 grams per 1000 grams of oleic acid.
4. Flavored Olive Oil
They are oils obtained by diversifying olive oils by adding different spices, fruits and vegetables or their natural flavorings.
Obtaining Olive Oil from Olive
1. Production Types
Two different methods are used in olive oil production: classical systems (press) and modern systems (centrifuge). While the presses are divided into two as hydraulic and super presses, they are divided into two as three and three phase systems in continuous systems. In the transition from classical systems to continuous systems; The main goal was to reduce olive processing costs, especially labor costs and reduce the waiting time of olives in the garden / warehouses and to improve olive oil quality by using high capacity decanters.
1. Workflow in Olive Oil Processing
The acceptance of olives
Olives coming to the facility and being accepted are required to be cleaned from stones, soil and foreign substances and must be washed before processing. Foreign substances not only reduce the quality of the oil, but also have a negative effect on sensory properties such as taste and smell.
Leaf separation and washing
Olives, which are free from foreign matter and washed, are subjected to crushing and crushing process to reveal the oil droplets in their cells. For this, stone or metal mills (crushers) are used. In classical systems, stone mills are generally used, whereas in continuous systems, metal mills / crushers are preferred. In addition to the advantages such as metal crushers, high capacity, small footprint, ease of use, and economical, disadvantages such as the risk of emulsion due to high speed, the risk of metal parts being worn out, and longer dough / malaxer time due to the cells not breaking down exactly like in stone mills. It has.
Break
It should be kneaded, especially when metal mills are used after the olive is crushed. This process is an important step in preparing the dough for the subsequent separation of solid / liquid phases. Two important parameters to be considered during kneading are kneading time and dough temperature. In terms of quality and efficiency, the optimum kneading time should be 75-90 minutes and the dough temperature should be maximum 30 ° C.
Kneading
Presses or machines called decanters are used to separate the oil phase in the olive paste, which is completed by kneading. Decanters used in continuous systems can have two or three outputs. Systems that come out of oil, blackwater and pomace are called "three-phase", while systems that emit only oil and pomace are called "two-phase".
Solid / liquid phase separation
In addition, percussion (selective filtration) system is used in olive oil production, based on the principle of obtaining oil from olives and having different surface tension compared to steel blades. After oil is obtained by percussion method, the remaining part is passed through presses or decanters again. Because with this method, only 30% of the oil in olive pulp can be taken.
Liquid / liquid phase separation
After the solid / liquid phase separation, since the oil obtained contains some black water, it is passed through separators for the liquid / liquid phase separation, purified from the black water and foreign substances in it, and sent to the warehouses by obtaining a cleaner oil.