Low oxygen storage impacts on blueberry fruit quality

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 modified atmosphere conditions. Thirty-nine blueberry accessions, representing different species of Vaccinium, were assessed at harvest and after six and eight weeks of storage at 2°C under normal and modified atmosphere (18% CO2: 7% O2), respectively. Besides the analytical assessment of the main quality traits – such as soluble solids, acidity, colour and weight loss – the aroma and texture development were accurately monitored by a proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS) and a texture analyzer. Results revealed an extremely high variability among Vaccinium genotypes for all investigated quality traits. In particular, the variability observed at harvest for both texture and VOCs profile was magnified during storage, especially under modified atmosphere condition. The response to cold storage of each genotype is reflected by contrasting changes especially for VOCs and texture. For most of the blueberry cultivars low oxygen storage intensifies the positive effect of cold storage reducing the texture decay and the water loss, and, at the same time, improving the VOC profile characterized by higher concentration of several ester compounds. Results obtained in this investigation provide 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