Changes in Anthocyanin and Antioxidant Contents during Maturation of Australian Highbush Blueberry (Vaccinium corymbosum L.) Cultivars

The Australian blueberry industry is worth over $300 million, but there limited information on factors influencing their chemical composition, particularly ripeness and harvest stage. This pilot study investigated changes in total monomeric anthocyanin content (TMAC; measured using the pH-differential method) antioxidant capacity (TAC; with cupric reducing assay) of four highbush cultivars (Denise, Blue Rose, Brigitta Bluecrop) at time points three maturity stages (unripe, moderately ripe fully ripe). TAC most decreased by 8–18% during ripening, although that Rose cultivar increased markedly. However, fruit from this also fluctuated markedly throughout season (between 1168–2171 mg Trolox equivalents 100 g−1). TMAC sharply between medium-ripe stages, showing highest values (211 g−1, compared to 107–143 g−1 for remaining varieties). rose steadily season, contrast other where fell slightly time. These results indicate levels health-benefitting compounds Australian-grown blueberries may depend not only cultivar, upon harvest.