Abstract:

Blueberries were stored under unsealed packaging, modified-atmosphere packaging (MAP) or common cold
conditions (control) at (0.5 ± 0.5) ℃ and 90%–95% relative humidity (RH). Physiological parameters such as soluble solid
content (SSC), ascorbic acid (VC), titratable acidity, polyphenol oxidase (PPO), peroxidase (POD), anthocyanin content, pectin
and polygalacturonase (PG) were monitored periodically during storage to compare the effectiveness of the three packaging
methods for preserving blueberries. After 49 days of storage, VC content, fruit firmness and titration acid content in the MAP
group were maintained at a significantly higher level as compared to the other two groups. There was no significant difference
among the three groups for soluble solid content. Nevertheless, MAP inhibited PG activity and accordingly reduced the
decomposition of pectin in blueberries; meanwhile, MAP maintained a higher level of POD activity so that the metabolismrelated
free radicals could be removed in a timely manner, delaying fruit senescence and prolonging the shelf life of blueberries.
In conclusion, MAP is more effective in preserving blueberries than unsealed packaging and common cold storage.

Key words: blueberry, MAP storage, post-harvest physiology, storage effect