Tailored storage management can positively affect blueberry fruit quality

Fruit postharvest is traditionally investigated in terms of flavor and texture because of their crucial impact on fruit acceptability and consumer satisfaction. Blueberry (Vaccinium spp.) edible quality highly depends on cultivar genetics, postharvest handling and storage conditions. The aim of this research was to unravel the variability of the main quality traits of Vaccinium germplasm, with attention to fruit quality changes during storage under different atmospheric storage conditions. Forty blueberry accessions, representing different Vaccinium species, were assessed at harvest and after six and eight weeks of storage at 4 °C under normal and modified atmosphere (18% CO2: 7% O2). Besides the analytical assessment of the main quality traits -such as soluble solids, acidity, texture, color and weight loss- the aroma was accurately monitored by PTR-ToF-MS (proton transfer reaction—time of flight—mass spectrometry) and SPME-GC-MS (solid phase microextraction- gas chromatography-mass spectrometry). In addition, a deeper investigation of four selected blueberry cultivars (Brigitta Blue, Centurion, Northland, and Star) has been performed during two months of storage under four atmosphere conditions (O2 concentrations: 21%, 12%, 7% and 1%). Results revealed an extremely high variability on quality among Vaccinium genotypes, especially for VOCs. This variability was magnified during storage especially at low oxygen condition, since several esters are synthesized ex-novo. The synthesis of these compounds may be the result of a fruit-specific process to prevent the over accumulation of ethanol, caused by anoxic stress. This investigation provides explanatory information for an optimized market segmentation, such as for domestic and export, and parental choice for those breeding programs aimed to enhance fruit quality and storability of blueberries