In addition to VOO, olive pomace oil can be obtained by treatment of the residue
or olive pomace, once VOO has been mechanically extracted. Olive pomace oil is
obtained by solvent extraction and has to undergo refinement.
The following products can be obtained from the lipid fraction of the olive fruit:
olive pomace oil, refined olive oil, olive oil, lampante olive oil, virgin olive oil
(VOO), extra virgin olive oil (EVOO). Additionally, the International Olive Council
(IOC) recognises another category named ordinary olive oil, which ranks between
“virgin olive oil” and “lampante olive oil”. Virgin olive oil is obtained by solvent
extraction of the residue contained in the solids after the extraction of virgin olive
oils. “Olive oil” is defined as the mixture of virgin olive oil with a non-well-defined
amount of refined olive oil. The latter cannot be sold to the final consumer as it is, but
it is used commercially for the preparation of admixtures with virgin olive oils.
Similarly, consumers do not find “lampante olive oil” in the retail market. Lampante
olive oil is obtained by mechanical extraction only but has such low-quality indices
that cannot be consumed directly. VOO and EVOO are the top products in the family
of oils obtained from the olive fruit. They are exclusively obtained by means of
physical extraction of the oil fraction from the olive fruits. EVOO has more
restrictive limits related to its physical properties and chemical composition and
particularly to its sensory characteristics. Poor physical and chemical indices may be
due to low-quality olive fruits, poor pre-extraction handling, incorrect extraction
conditions or poor storage and packaging of the oil.
9.3 Chemical Composition
Extensive literature reports are available on olive oil composition(Aparicio &
Harwood 2013); therefore, this paragraph will just give a brief summary and focus
on the most prominent compounds. For a comprehensive overview on the topic, the
reader can refer to Lanza (2012) and Boskou et al. (2006).
Olive oil—contrary to other vegetable fats which usually derive from seeds—is
obtained from a fruit. The olive fruit is a drupe, which can be classified into two
parts, namely, flesh and seed.
The major olive components are water (40–70%) and fat (6–25%), mainly present
in the mesocarp. The fruit also contains simple sugars (2–5%), represented by
glucose, fructose and mannose (Montaño et al. 2010). Other components are cellulose (approximately 6%), protein (1–2%) and ash (1–2%). Organic acids, nitrogen
compounds, flavonoids and anthocyanins are also present in olive fruits. Particularly
important for olive composition is the phenolic fraction, mainly constituted by
oleuropein, dimethyloleuropein and verbascoside. These compounds are present in
concentrations between 0.5% and 2.5% of the fresh weight. The oil fraction is
present as oil droplet in the pulp (16.5–23.5% fresh weight), while small amounts
are also found in the seed (1–1.5%).
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or olive pomace, once VOO has been mechanically extracted. Olive pomace oil is
obtained by solvent extraction and has to undergo refinement.
The following products can be obtained from the lipid fraction of the olive fruit:
olive pomace oil, refined olive oil, olive oil, lampante olive oil, virgin olive oil
(VOO), extra virgin olive oil (EVOO). Additionally, the International Olive Council
(IOC) recognises another category named ordinary olive oil, which ranks between
“virgin olive oil” and “lampante olive oil”. Virgin olive oil is obtained by solvent
extraction of the residue contained in the solids after the extraction of virgin olive
oils. “Olive oil” is defined as the mixture of virgin olive oil with a non-well-defined
amount of refined olive oil. The latter cannot be sold to the final consumer as it is, but
it is used commercially for the preparation of admixtures with virgin olive oils.
Similarly, consumers do not find “lampante olive oil” in the retail market. Lampante
olive oil is obtained by mechanical extraction only but has such low-quality indices
that cannot be consumed directly. VOO and EVOO are the top products in the family
of oils obtained from the olive fruit. They are exclusively obtained by means of
physical extraction of the oil fraction from the olive fruits. EVOO has more
restrictive limits related to its physical properties and chemical composition and
particularly to its sensory characteristics. Poor physical and chemical indices may be
due to low-quality olive fruits, poor pre-extraction handling, incorrect extraction
conditions or poor storage and packaging of the oil.
9.3 Chemical Composition
Extensive literature reports are available on olive oil composition(Aparicio &
Harwood 2013); therefore, this paragraph will just give a brief summary and focus
on the most prominent compounds. For a comprehensive overview on the topic, the
reader can refer to Lanza (2012) and Boskou et al. (2006).
Olive oil—contrary to other vegetable fats which usually derive from seeds—is
obtained from a fruit. The olive fruit is a drupe, which can be classified into two
parts, namely, flesh and seed.
The major olive components are water (40–70%) and fat (6–25%), mainly present
in the mesocarp. The fruit also contains simple sugars (2–5%), represented by
glucose, fructose and mannose (Montaño et al. 2010). Other components are cellulose (approximately 6%), protein (1–2%) and ash (1–2%). Organic acids, nitrogen
compounds, flavonoids and anthocyanins are also present in olive fruits. Particularly
important for olive composition is the phenolic fraction, mainly constituted by
oleuropein, dimethyloleuropein and verbascoside. These compounds are present in
concentrations between 0.5% and 2.5% of the fresh weight. The oil fraction is
present as oil droplet in the pulp (16.5–23.5% fresh weight), while small amounts
are also found in the seed (1–1.5%).
214
N. Caporaso and D. Boskou