Factors affecting blueberry physical-chemical properties

The objective of this work is to investigate the effect of different production and conservation factors on the properties of blueberries. The production factors considered were cultivar (Duke, Bluecrop, Ozarkblue) and production mode (organic or conventional). The conservation factors were temperature (ambient, refrigeration) and time (0, 7, 14 days). The properties under study were: physical properties (color and texture); some chemical components (moisture content, sugars and acidity) and phenolic and antioxidant properties (total phenols, anthocyanins, tannins, ABTS antioxidant activity, DPPH antioxidant activity). This work showed that moisture content was only influenced by cultivar and that both acidity and sugar contents varied according to the production mode used. The results evidenced that the antioxidant activity was not statistically different according to cultivar, production mode or conservation. As to the phenolics, only tannins showed significant differences according to production mode, being higher for organic farming. Color parameters showed some significant differences, so that the most intense blue corresponded to blueberries from cv. Duke, form organic farming and stored under refrigeration. Texture was also very significantly influenced by the three factors at study, cultivar, production mode and conservation, being the berries with higher firmness those from cultivar Duke and stored under refrigeration