Phenolic profile and antioxidant activity of highbush blueberry (Vaccinium corymbosum L.) during fruit maturation and ripening

The phenolic profile and quantitative composition of blueberries as well as the corresponding antioxidant activity of blueberries is well documented. Unfortunately, little is reported on the development of phenolic compounds and antioxidant activity during fruit maturation and ripening. In the present study, the total phenolic content and main phenolic compounds of four highbush blueberry cultivars (Vaccinium corymbosum L.) were analyzed at five stages of maturation and ripening. Antioxidant activity was screened with electron spin resonance spectrometry and trolox equivalent antioxidant capacity (TEAC) assay. An adequate picture of phenolic compounds developed during maturation and ripening was determined using HPLC-DAD. Anthocyanins of all varieties increased during successive harvest stages; meanwhile flavonols and hydroxycinnamic acids decreased from unripe green to ripe blue stage of berry ripening. Blueberry antioxidant activity, as well as total phenolic content tended to decrease during ripening.