1.3 Phenols, Their Chemical Structures, Sourcing and Interactions …
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Among them, phenolic acids constitute about one-third of the dietary phenols and
are present in plants in free and bound forms (Robbins 2003). Kumar and colleagues
claimed, based on their statistical observation, that in most of the plants they examined
caffeic acid and quercetin were predominant (Kumar et al. 2019). On the other hand,
phenolic acids and flavonols are the major functional food components occurring
in fruits (Lodovici et al. 2001; Scalbert and Williamson 2000). In live plants, the
role of phenols is variable and diverse, e.g. attractants for pollinators, contributors to
plant pigmentation, antifeedants,
3 antioxidants, phytoalexins
4 and protectors against
ultraviolet (UV) light and atmospheric pollution (Lombardo et al. 2012).
Furthermore, when a part of a food matrix, phenols impact flavour, colour, odour,
bitterness, astringency, and the oxidative stability of the food product. Polyphenols
may have beneficial (as a nutrient or nutraceutical) or somewhat adverse effects (as
antinutrients). In their review ‘Risks and polyphenols consumption’, Mennen and colleagues explained in deep the importance of defining the probability of detrimental
effects of phenols to occur, in order to optimize the dose/level for human consumption (Mennen et al. 2005). Polyphenols are found in a wide range of plant-derived
foodstuffs and drinks. These phytochemicals are relatively unstable and very sensitive to changes stimulated by pedoclimatic, varietal, technological factors and even
by the stage of maturation (of fruits) and storage conditions, as well as processing,
and culinary preparations.
1.3.2 Polyphenols. Sources and Interactions
The sources of polyphenols in the diet include a wide variety of fresh plant foods,
foodstuffs derived from them and beverages, i.e. peaches, pomegranate, grapes,
oranges, reddish, garlic, nuts, table olives, citrus, EVOO, cocoa powder, dark chocolate, herbal infusions and among many others (Bhagat et al. 2019; Parisi 2019–2020;
Zugravu and Otelea 2019).
1.3.3 Phenols and Genetic Variability
Rigacci and Stefani (2016) have classified olive cultivars in three groups, based on
their richness in polyphenols. The first group has the highest concentration of more
than 600 mg of total polyphenols/kg of olive oil (examples of such olive cultivars
3 An organic compound produced by plants to inhibit the attack by insects. It has an activity and a
chemical structure similar to those of biopesticide.
4 Antimicrobial and antioxidant molecules that are synthesized by plants as part of their defence
mechanism against pathogen attack.
7
Among them, phenolic acids constitute about one-third of the dietary phenols and
are present in plants in free and bound forms (Robbins 2003). Kumar and colleagues
claimed, based on their statistical observation, that in most of the plants they examined
caffeic acid and quercetin were predominant (Kumar et al. 2019). On the other hand,
phenolic acids and flavonols are the major functional food components occurring
in fruits (Lodovici et al. 2001; Scalbert and Williamson 2000). In live plants, the
role of phenols is variable and diverse, e.g. attractants for pollinators, contributors to
plant pigmentation, antifeedants,
3 antioxidants, phytoalexins
4 and protectors against
ultraviolet (UV) light and atmospheric pollution (Lombardo et al. 2012).
Furthermore, when a part of a food matrix, phenols impact flavour, colour, odour,
bitterness, astringency, and the oxidative stability of the food product. Polyphenols
may have beneficial (as a nutrient or nutraceutical) or somewhat adverse effects (as
antinutrients). In their review ‘Risks and polyphenols consumption’, Mennen and colleagues explained in deep the importance of defining the probability of detrimental
effects of phenols to occur, in order to optimize the dose/level for human consumption (Mennen et al. 2005). Polyphenols are found in a wide range of plant-derived
foodstuffs and drinks. These phytochemicals are relatively unstable and very sensitive to changes stimulated by pedoclimatic, varietal, technological factors and even
by the stage of maturation (of fruits) and storage conditions, as well as processing,
and culinary preparations.
1.3.2 Polyphenols. Sources and Interactions
The sources of polyphenols in the diet include a wide variety of fresh plant foods,
foodstuffs derived from them and beverages, i.e. peaches, pomegranate, grapes,
oranges, reddish, garlic, nuts, table olives, citrus, EVOO, cocoa powder, dark chocolate, herbal infusions and among many others (Bhagat et al. 2019; Parisi 2019–2020;
Zugravu and Otelea 2019).
1.3.3 Phenols and Genetic Variability
Rigacci and Stefani (2016) have classified olive cultivars in three groups, based on
their richness in polyphenols. The first group has the highest concentration of more
than 600 mg of total polyphenols/kg of olive oil (examples of such olive cultivars
3 An organic compound produced by plants to inhibit the attack by insects. It has an activity and a
chemical structure similar to those of biopesticide.
4 Antimicrobial and antioxidant molecules that are synthesized by plants as part of their defence
mechanism against pathogen attack.