Olive oil ProductionOlive oil ProductionSpanish olive oilSpanish olive oil

Obtaining virgin oilsObtaining virgin oils• Olive treeOlive tree

– Typical mediterraneanTypical mediterranean– Slowly growSlowly grow– Fully productive ages: 35-100 yearsFully productive ages: 35-100 years

FlowsheetFlowsheet• Olive treeOlive tree• OliveOlive• TransportTransport• MillMill

– WashingWashing– CrushingCrushing– GrindlingGrindling

• Press/Press/centrifuguecentrifugue– pressingpressing– centrifugationcentrifugation– decantationdecantation

• Virgin olive oilVirgin olive oil• StorageStorage

1. Harvesting the fruit1. Harvesting the fruit• Olives trees flower in springOlives trees flower in spring• Change from green to blackChange from green to black• End autumm/beginning winter harvestEnd autumm/beginning winter harvest

- picked by hand or beaten from the - picked by hand or beaten from the trees with “baras”trees with “baras”-mechanical tree shaking methods-mechanical tree shaking methods

2. Transport to the oil mill2. Transport to the oil mill• The olives must be free of stonesThe olives must be free of stones

– To avoid braking the skin, as this would To avoid braking the skin, as this would lead the beginning of the fermentationlead the beginning of the fermentation

• The olives must not be piled up high The olives must not be piled up high or else they will heat up and start to or else they will heat up and start to ferment. ferment.

• Olives must be processed within 24 Olives must be processed within 24 hours after they are harvested to hours after they are harvested to obtain quality olive oilobtain quality olive oil

3. Washing3. Washing

• On the conveyor belt the leaves are On the conveyor belt the leaves are separated by an air currentseparated by an air current

• They are washed with normal water They are washed with normal water after they are selected for qualityafter they are selected for quality

4. Grinding to prepare the 4. Grinding to prepare the pastepaste• Grinding consists of crushing the fruit Grinding consists of crushing the fruit

(including the pits - ?) until a paste is (including the pits - ?) until a paste is formed which is then beaten. Water formed which is then beaten. Water is added if necessary. is added if necessary.

5. Separation of solid and 5. Separation of solid and liquid phases (oil extraction)liquid phases (oil extraction)• Several methods, but it is essential that Several methods, but it is essential that

the temperature does not exceed 35º C the temperature does not exceed 35º C – Traditional system (pressing)Traditional system (pressing)

•Classic discontinuous plants Classic discontinuous plants – These are the classic plants maintained throughout These are the classic plants maintained throughout

the centuries. The ground paste is placed between the centuries. The ground paste is placed between round mats and is then pressed to squeeze out the round mats and is then pressed to squeeze out the oily liquid (mixture of oil and water). It is later left to oily liquid (mixture of oil and water). It is later left to decant, as the oil floats to the top due to density decant, as the oil floats to the top due to density differences. differences.

5. Separation of solid and 5. Separation of solid and liquid phases (oil extraction)liquid phases (oil extraction)• Continuous system (by centrifugation)Continuous system (by centrifugation) • Continuous plants in 3 phases Continuous plants in 3 phases

– The beaten olive paste is made more liquid by The beaten olive paste is made more liquid by adding 1 litre of water per kilogram of paste and adding 1 litre of water per kilogram of paste and is taken to a horizontal centrifuge where solids is taken to a horizontal centrifuge where solids are separated from the oily liquid. This liquid is are separated from the oily liquid. This liquid is then taken to a vertical centrifuge where the then taken to a vertical centrifuge where the olive oil is separated from the fruit vegetable olive oil is separated from the fruit vegetable water. water.

• Continuous plants in 2 phases Continuous plants in 2 phases – The process is practically the same as the one The process is practically the same as the one

described above, with the difference that instead described above, with the difference that instead of adding water for the horizontal centrifugation, of adding water for the horizontal centrifugation, the vegetable water is recycled. the vegetable water is recycled.

Advantages of the continuous Advantages of the continuous system system • High production capacity, which avoids High production capacity, which avoids

having a stock of olives and therefore having a stock of olives and therefore increases the oil's quality increases the oil's quality

• Improves performance, cleanliness and Improves performance, cleanliness and hygiene hygiene

• In the 2 phase plants, recycling the In the 2 phase plants, recycling the vegetable water means the oil has a larger vegetable water means the oil has a larger quantity of polyphenols, natural protectors quantity of polyphenols, natural protectors against oxidation against oxidation

6. Storage 6. Storage • Walls and ceilings insulate against Walls and ceilings insulate against

high temperatures and which does high temperatures and which does not add strange smells to the oil. not add strange smells to the oil.

• Temperature is between 15 and 18º Temperature is between 15 and 18º C to allow the oils to mature without C to allow the oils to mature without oxidation. oxidation.

• There must not be much light.There must not be much light.

Non Virgin OilsNon Virgin Oils•RefiningRefining

– Due to climate conditions, the type of Due to climate conditions, the type of soil and so on, virgin oils can have soil and so on, virgin oils can have several defects, such as high acidity, a several defects, such as high acidity, a strange colour or aroma, etc. which strange colour or aroma, etc. which makes them unsuitable for human makes them unsuitable for human consumption ("lampante oils"). They consumption ("lampante oils"). They have to undergo a refining process to have to undergo a refining process to eliminate defects.eliminate defects.

RefiningRefining• 1. Classic alkaline refining1. Classic alkaline refining

– This has 3 phases. Each one tends to eliminate This has 3 phases. Each one tends to eliminate a specific process: a specific process:

-neutralisation-neutralisation-bleaching-bleaching-deodorisation-deodorisation

• 2. Physical refining2. Physical refining– It is different from the previous method as acid It is different from the previous method as acid

water is used instead of soda to purify the oil water is used instead of soda to purify the oil and the temperature is higher. and the temperature is higher.

Kinds of olive oils (Virgin oil)Kinds of olive oils (Virgin oil)• Extra virgin olive oil: virgin olive oil which has a Extra virgin olive oil: virgin olive oil which has a

free acidity, expressed as oleic acid, of not more free acidity, expressed as oleic acid, of not more than 0.8 grams per 100 gramsthan 0.8 grams per 100 grams

• Virgin olive oil: virgin olive oil which has a free Virgin olive oil: virgin olive oil which has a free acidity, expressed as oleic acid, of not more than acidity, expressed as oleic acid, of not more than 2 grams per 100 grams 2 grams per 100 grams

• Ordinary virgin olive oil: virgin olive oil which has Ordinary virgin olive oil: virgin olive oil which has a free acidity, expressed as oleic acid, of not more a free acidity, expressed as oleic acid, of not more than 3.3 grams per 100 gramsthan 3.3 grams per 100 grams

• Virgin olive oil not fit for consumption as it is, Virgin olive oil not fit for consumption as it is, designated lampante virgin olive oil, is virgin olive designated lampante virgin olive oil, is virgin olive oil which has a free acidity, expressed as oleic oil which has a free acidity, expressed as oleic acid, of more than 3.3 grams acid, of more than 3.3 grams

Kinds of oils (refined oils)Kinds of oils (refined oils)• Refined olive oil is the olive oil obtained from virgin olive oils Refined olive oil is the olive oil obtained from virgin olive oils

by refining methods which do not lead to alterations in the by refining methods which do not lead to alterations in the initial glyceridic structure. It has a free acidity, expressed as initial glyceridic structure. It has a free acidity, expressed as oleic acid, of not more than 0.3 grams per 100 gramsoleic acid, of not more than 0.3 grams per 100 grams

• Olive oil is the oil consisting of a blend of refined olive oil Olive oil is the oil consisting of a blend of refined olive oil and virgin olive oils fit for consumption as they are. It has a and virgin olive oils fit for consumption as they are. It has a free acidity, expressed as oleic acid, of not more than 1 free acidity, expressed as oleic acid, of not more than 1 gram per 100 gramsgram per 100 grams

• Olive-pomace oil is the oil obtained by treating olive pomace Olive-pomace oil is the oil obtained by treating olive pomace with solvents or other physical treatments, to the exclusion with solvents or other physical treatments, to the exclusion of oils obtained by re esterification processes and of any of oils obtained by re esterification processes and of any mixture with oils of other kinds. It is marketed in accordance mixture with oils of other kinds. It is marketed in accordance with the following designations and definitions: with the following designations and definitions: – Crude olive-pomace oil Crude olive-pomace oil – Refined olive pomace oil Refined olive pomace oil