Phenolic compounds of 'Galega Vulgar' and 'Cobrançosa' olive oils along early ripening stages.
In this study, the lipophilic and hydrophilic phenol composition of virgin olive oils (VOO) obtained from olives from two of the most important Portuguese cultivars ('Galega Vulgar' and 'Cobrançosa'), harvested at different ripening stages and under two irrigation schemes (rain fed and irrigated), was evaluated. Phenolic alcohols (hydroxytyrosol and tyrosol), phenolic acids and derivatives and flavonoids (luteolin and apigenin), as well as tocopherols were quantified. Lipophilic (>300mgkg(-1)) and hydrophilic phenols (>600mgkg(-1)) were present in high contents in both VOO, for early ripening stages. Gamma-tocopherol content is higher in 'Galega Vulgar' VOO. Total phenols showed a decrease between ripening index 2.5 and 3.5. The dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA), also known as oleacein, was the major phenolic compound identified in both oils. The concentration of free hydroxytyrosol and tyrosol in both VOO is very low while their esterified derivatives, like 3,4-DHPEA-EDA and p-HPEA-EDA, are much more abundant.
Instituto Politécnico de Castelo Branco, Escola Superior Agrária, 6001-909 Castelo Branco, Portugal.
Fátima
F
Peres
Universidade de Lisboa, Instituto Superior de Agronomia, LEAF, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
Luisa L
LL
Martins
Universidade de Lisboa, Instituto Superior de Agronomia, LEAF, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
Miguel
M
Mourato
Instituto Politécnico de Castelo Branco, Escola Superior Agrária, 6001-909 Castelo Branco, Portugal.
Conceição
C
Vitorino
CATAA, Centro de Apoio Tecnológico Agro-Alimentar de Castelo Branco, 6000-459 Castelo Branco, Portugal.
Paulo
P
Antunes
Universidade de Lisboa, Instituto Superior de Agronomia, LEAF, Tapada da Ajuda, 1349-017 Lisbon, Portugal. Electronic address: suzanafdias@mail.telepac.pt.
Suzana
S
Ferreira-Dias
D062385:Hydroxybenzoates; D000069463:Olive Oil / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry*; D024505:Tocopherols
D062385:Hydroxybenzoates; D000069463:Olive Oil; D010938:Plant Oils; C017616:phenolic acid; D024505:Tocopherols
Oleacein; Oxidative stability; Phenols; Tocopherols; Virgin olive oils