oleuropein and other forms of the oleuropein aglycone; the “pungent” note has been
attributed to the aglycone from the dialdehydic form of the decarboxymethyl
ligstroside (Servili et al. 2009).
The sensory defect of “winey-vinegary” is associated with fermentative processes
especially from Lactobacillus, when olives are left on the ground for prolonged
times. The consequent production of acetic acid has been indicated as a marker of
olives collected from the ground. A high concentration of acetic acid and octane was
correlated to the defect of “reheating”, a consequence of the activity of
Enterobacteriaceae of the genus Aerobacter and Escherichia. The genera Pseudomonas, Clostridium and Serratia appear if the olives are left in bags for a long time
after harvesting. The activity of these microorganisms results in the presence of some
volatile compounds at high concentrations. The defect of “mould-humidity” has
been correlated to the presence of 3-methyl-1-butanol.
Other compounds that would be important in defining the overall aroma oil have
been reported to occur in low concentrations in the olive paste: hexyl acetate (fruity
odour) could be a marker of good quality oils, but it does not contribute to the aroma
of the paste due to its high perception threshold (~1.04 mg/kg) and low concentration in the paste (maximum 1.00 mg/kg) (Garcia-Gonzales et al. 2007).
9.7 Food Applications
The use of olive oil is solely found as a condiment, which means that different from
other products such as wine or cheese, it is never consumed by itself. The versatility
of its use as a condiment or ingredient makes it difficult to choose the most
appropriate type of olive oil for different recipes or dishes.
Olive oil can be used as a “raw” ingredient or for cooking. It can be included into
baked goods and used for stir-frying or deep-frying. In the traditional area where
olives are grown, i.e. around the Mediterranean Basin, olive oil is the main fat used
in a wide range of food preparations. EVOO, the top category within the olive oil
family, is often used as raw (without the application of high temperatures) to avoid
degradation of phenolic compounds and loss of aroma during cooking; however,
there is no harm in using it even for frying (Saghir et al. 2005). In this case, attention
should be paid not to excessively heat the oil, as the presence of a small amount of
residual water and solid particles (especially in unfiltered oil) slightly lower the
so-called smoking point (Galeone et al. 2006). In terms of stability during prolonged
heating, olive oil generally shows good stability due to its high content of oleic acid
and the presence of natural antioxidants.
Olive oil can be used in salads or mixed into dressings; it can be applied to meat
of fish for marinades or can be add at the end of a dish preparation to impart extra
flavour and appearance. Due to its health benefits, it can also replace butter,
margarine or other animal fats. Similarly, it can be used in sauces instead of other
vegetable oils, giving a nutritionally balanced product with a unique flavour.
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N. Caporaso and D. Boskou
attributed to the aglycone from the dialdehydic form of the decarboxymethyl
ligstroside (Servili et al. 2009).
The sensory defect of “winey-vinegary” is associated with fermentative processes
especially from Lactobacillus, when olives are left on the ground for prolonged
times. The consequent production of acetic acid has been indicated as a marker of
olives collected from the ground. A high concentration of acetic acid and octane was
correlated to the defect of “reheating”, a consequence of the activity of
Enterobacteriaceae of the genus Aerobacter and Escherichia. The genera Pseudomonas, Clostridium and Serratia appear if the olives are left in bags for a long time
after harvesting. The activity of these microorganisms results in the presence of some
volatile compounds at high concentrations. The defect of “mould-humidity” has
been correlated to the presence of 3-methyl-1-butanol.
Other compounds that would be important in defining the overall aroma oil have
been reported to occur in low concentrations in the olive paste: hexyl acetate (fruity
odour) could be a marker of good quality oils, but it does not contribute to the aroma
of the paste due to its high perception threshold (~1.04 mg/kg) and low concentration in the paste (maximum 1.00 mg/kg) (Garcia-Gonzales et al. 2007).
9.7 Food Applications
The use of olive oil is solely found as a condiment, which means that different from
other products such as wine or cheese, it is never consumed by itself. The versatility
of its use as a condiment or ingredient makes it difficult to choose the most
appropriate type of olive oil for different recipes or dishes.
Olive oil can be used as a “raw” ingredient or for cooking. It can be included into
baked goods and used for stir-frying or deep-frying. In the traditional area where
olives are grown, i.e. around the Mediterranean Basin, olive oil is the main fat used
in a wide range of food preparations. EVOO, the top category within the olive oil
family, is often used as raw (without the application of high temperatures) to avoid
degradation of phenolic compounds and loss of aroma during cooking; however,
there is no harm in using it even for frying (Saghir et al. 2005). In this case, attention
should be paid not to excessively heat the oil, as the presence of a small amount of
residual water and solid particles (especially in unfiltered oil) slightly lower the
so-called smoking point (Galeone et al. 2006). In terms of stability during prolonged
heating, olive oil generally shows good stability due to its high content of oleic acid
and the presence of natural antioxidants.
Olive oil can be used in salads or mixed into dressings; it can be applied to meat
of fish for marinades or can be add at the end of a dish preparation to impart extra
flavour and appearance. Due to its health benefits, it can also replace butter,
margarine or other animal fats. Similarly, it can be used in sauces instead of other
vegetable oils, giving a nutritionally balanced product with a unique flavour.
238
N. Caporaso and D. Boskou