Quality changes of highbush blueberries fruit stored in CA with different CO levels

Quality changes of blueberries (Vacccinium corymbosum L. cv Brigitta) were evaluated during CA storage (0 degrees C) with different concentrations of CO(2) (5%, 10%, and 15%) combined with 5% O(2), respectively. Atmospheric air (20.9% O(2)+ 0.03% CO(2)) was used as control. From samples taken at 0, 24, and 48 d of storage, unmarketable fruits and weight loss were recorded as well as color (h), firmness (g), soluble solid content (%), titratable acidity (% citric acid), ratio, and the monomeric anthocyanin content (ppm). At each sampling time, additional units were kept for 3 d at 10 degrees C to simulate retail holding conditions. Irrespective of gas concentration, 0.9% of the initial fresh weight was lost after 48 d at 0 degrees C. CA fruit had better quality than control at the 24 d sampling but due to the high number of unmarketable fruits, this advantage was not observed at 48 d at 0 degrees C. After 24 d of storage, fruits for CA treatments were more firm and had better color, with higher anthocyanin and acidity levels. Soluble solid content showed no significant differences throughout the cold storage period. Residual effect of CA storage was observed at the retail holding condition yielding better firmness, acidity, and ratio. However, the CO(2) level tested increased the number of unmarketable fruit in long-term storage (48 d). Response of "Brigitta" blueberries to the different CO(2) levels studied was moderate and could be related to the high storage potential of this cultivar.