Chemical characterization and evaluation of antioxidant properties of Açaí fruits (Euterpe oleraceae Mart.) during ripening

► A decrease of phenolic compounds (besides anthocyanins which increased) was observed by HPLC-MS/MS in the course of ripening. ► A decrease of the antioxidant capacity (assessed by TEAC and TOSC) was observed during ripening. ► Contribution of identified polyphenols to overall antioxidant capacity was not significant (assessed by authentic standards). ► A decrease of determined nutrients during ripening was observed (besides lipids which increased).