Ascorbic acid content and senescence in blueberry (Vaccinium corymbosum L.) during storage

Blueberry consumption increases because its health properties linked to antioxidants, easy cultivation and profitability. The ability to preserve fruits in controlled atmosphere (CA) allows extending the marketing calendar. The work evaluates parameters linked to the cellular redox state of blueberry fruits, cv. Brigitta, stored at 0°C at different atmosphere regimes (CA1= 10% CO2, 4% O2 and CA2= 9% CO2, 2% O2, compared to air as control). During storage, quality was assessed by the content of ascorbic acid (AA), antioxidant and index of fruit metabolic status, and of malondialdehyde (MDA), cell membranes oxidative stress and senescence marker; soluble solids content, titratable acidity and dry matter were also determined. Storage in CA increases the blueberries shelf life, particularly at the intermediate times; after 2 months there is a drastic lowering in AA levels and differences among treatments are no longer detectable. Ascorbate is confirmed to be an excellent index of oxidative stress in fruit senescence processes. In control, along with the AA decrease, there is a higher MDA content, in particular up to the intermediate dates. CA2 proves to be the most suitable atmosphere for delaying the senescence process. Titratable acidity and soluble solids remain constant in all samples throughout storage.