Phenolic compounds. Phenolic compounds were analysed
using the Folin–Ciocalteau method (Singleton, Orthofer, &
Lamuela-Raventos, 1999) with slight modifications. 40 lL of
extraction solution obtained in Section 2.3.4, plus 625 lL of distilled
water and 130 lL of Folin-Ciocaltaeau reagent were mixed
with a Vortex (Genie 2 Daigger, Scientific Industries Inc.