8
1 Polyphenols and the Mediterranean Diet …
are Coratina, Cornicabra, Coroneiki, Manzanilla), while the second group includes
cultivars with a medium concentration of polyphenols (e.g. Aglandau, Arbosana,
Ascolana, Bouteillan, Carolea). The last group contains cultivars with the lowest
level of polyphenols: less than 200 mg/kg of oil (e.g. Arbequina, Casaliva, Noccellara) (Rigacci and Stefani 2016). Issaoui and coworkers have studied the concentration of polyphenols and their relationship with antioxidant activity, on the
one side, and the relation between polyphenols and sensory analysis, on the other
side (Issaoui et al. 2009–2010). These authors observed that fruit varieties with
higher levels of polyphenols also have the highest capacity to scavenge free radicals
and display the highest sensorial positive attributes. This situation is observed when
speaking of cultivars such as Rekhami, Jarboui, Sayali and Chétoui. Esti et al. (1998)
have carried out a two-year’ study in order to understand the behaviour of phenolic
compounds occurred in olive fruit in nine olive varieties. Authors concluded that
demethyloleuropein could be used as a varietal biomarker (Esti et al. 1998).
As olives, also each apple cultivar has its own polyphenolic profile: ‘Antei’
cultivar has a higher level of polyphenols (38.0 mg/100 ml) than ‘Kulikovskoye’
(33.1 mg/100 ml), ‘Melba’ (34.1 mg/100 ml) and ‘Orlovski sinap’ (26.8 mg/100 ml)
(Laaksonen et al. 2017). According to an earlier study conducted by Soleas and
coworkers, some cultivars of Vitis vinifera such as Pinot Noir appear to have a great
intrinsic capacity to synthesize resveratrol, regardless of where or under what conditions they are grown (Soleas et al. 1997). Lombardo and colleagues have found that
the total polyphenol content of the whole artichoke head was significantly cultivardependent (Lombardo et al. 2012); the ‘Tema 2000’ type represented a rich source
of polyphenols with the highest content of the whole head (7.4 g/kg) followed by
‘Nobre’ (6.7 g/kg) and ‘Violetto di Sicilia clone 4/ 8’ (6.4 g/kg). On the other side, the
lowest values were found in ‘Tempo’ types with only 1.6 g/kg. In a previous study,
Lombardo and coworkers have studied the impact of genotype of nine artichokes
cultivated in Sicily on their phenolic content and profiles (Lombardo et al. 2010).
Their results exhibited a high variability in terms of total and individual phenolic
compounds between varieties. They have proved that phenols’ variability is detected
even inside the same artichoke but in different parts of the plant; hence, ‘Violetto di
Sicilia’ shows the highest total amount of polyphenols. As a result, the authors suggested that it may be used in pharmaceutical preparations. In contrast, ‘Romanesco
clone C3’ may be adequate enough for fresh consumption because it showed the
maximum contents of phenols in the receptacle. Thanks to their lower propensity to
browning during handling and storage and the lowest contents of total polyphenols
in outer and inner bracts, authors claimed that ‘Harmony F1’ and ‘Tondo di Paestum’
appear to be more adapted for food processing.
Distribution of phenolics in plant tissues at cellular and sub-cellular levels is very
heterogeneous. In fact, the concentration of phenols varied even in different organs of
the same plant, for instance ranging from 50 to 1000 mg/kg (Gorzynik-Debicka et al.
2018). Polyphenols in apples are much more abundant in the skin than in the pulp
(Mayr et al. 1995). Similarly, pistachio’ skin is a better source of polyphenols than
pistachios seeds. Skin contains 70.27 mg/kg (catechin equivalents) of total flavonoids
versus 0.46 mg/kg inside seeds (Tomaino et al. 2010).
1 Polyphenols and the Mediterranean Diet …
are Coratina, Cornicabra, Coroneiki, Manzanilla), while the second group includes
cultivars with a medium concentration of polyphenols (e.g. Aglandau, Arbosana,
Ascolana, Bouteillan, Carolea). The last group contains cultivars with the lowest
level of polyphenols: less than 200 mg/kg of oil (e.g. Arbequina, Casaliva, Noccellara) (Rigacci and Stefani 2016). Issaoui and coworkers have studied the concentration of polyphenols and their relationship with antioxidant activity, on the
one side, and the relation between polyphenols and sensory analysis, on the other
side (Issaoui et al. 2009–2010). These authors observed that fruit varieties with
higher levels of polyphenols also have the highest capacity to scavenge free radicals
and display the highest sensorial positive attributes. This situation is observed when
speaking of cultivars such as Rekhami, Jarboui, Sayali and Chétoui. Esti et al. (1998)
have carried out a two-year’ study in order to understand the behaviour of phenolic
compounds occurred in olive fruit in nine olive varieties. Authors concluded that
demethyloleuropein could be used as a varietal biomarker (Esti et al. 1998).
As olives, also each apple cultivar has its own polyphenolic profile: ‘Antei’
cultivar has a higher level of polyphenols (38.0 mg/100 ml) than ‘Kulikovskoye’
(33.1 mg/100 ml), ‘Melba’ (34.1 mg/100 ml) and ‘Orlovski sinap’ (26.8 mg/100 ml)
(Laaksonen et al. 2017). According to an earlier study conducted by Soleas and
coworkers, some cultivars of Vitis vinifera such as Pinot Noir appear to have a great
intrinsic capacity to synthesize resveratrol, regardless of where or under what conditions they are grown (Soleas et al. 1997). Lombardo and colleagues have found that
the total polyphenol content of the whole artichoke head was significantly cultivardependent (Lombardo et al. 2012); the ‘Tema 2000’ type represented a rich source
of polyphenols with the highest content of the whole head (7.4 g/kg) followed by
‘Nobre’ (6.7 g/kg) and ‘Violetto di Sicilia clone 4/ 8’ (6.4 g/kg). On the other side, the
lowest values were found in ‘Tempo’ types with only 1.6 g/kg. In a previous study,
Lombardo and coworkers have studied the impact of genotype of nine artichokes
cultivated in Sicily on their phenolic content and profiles (Lombardo et al. 2010).
Their results exhibited a high variability in terms of total and individual phenolic
compounds between varieties. They have proved that phenols’ variability is detected
even inside the same artichoke but in different parts of the plant; hence, ‘Violetto di
Sicilia’ shows the highest total amount of polyphenols. As a result, the authors suggested that it may be used in pharmaceutical preparations. In contrast, ‘Romanesco
clone C3’ may be adequate enough for fresh consumption because it showed the
maximum contents of phenols in the receptacle. Thanks to their lower propensity to
browning during handling and storage and the lowest contents of total polyphenols
in outer and inner bracts, authors claimed that ‘Harmony F1’ and ‘Tondo di Paestum’
appear to be more adapted for food processing.
Distribution of phenolics in plant tissues at cellular and sub-cellular levels is very
heterogeneous. In fact, the concentration of phenols varied even in different organs of
the same plant, for instance ranging from 50 to 1000 mg/kg (Gorzynik-Debicka et al.
2018). Polyphenols in apples are much more abundant in the skin than in the pulp
(Mayr et al. 1995). Similarly, pistachio’ skin is a better source of polyphenols than
pistachios seeds. Skin contains 70.27 mg/kg (catechin equivalents) of total flavonoids
versus 0.46 mg/kg inside seeds (Tomaino et al. 2010).