Physicochemical Evolution of Blueberries during Extended Frozen Storage at -۲۰°C: Implications for Shelf Life and Quality Preservation

Blueberry (Vaccinium spp.) is well-known for its high antioxidant capacity and exceptional richness of vitamins, fiber, and polyphenols. Due to its bioactive compounds including flavonoids, tannins, and phenolic acids, blueberry possesses various health benefits such as anti-diabetic, anti-cardiovascular, and anti-carcinogenic properties. However, its limited production period, and short shelf-life, generate a huge quantity of post-harvest losses. In this context, a set of post-harvest treatments are necessary, to extend the shelf life of blueberries and promote their consumption throughout the year. In this regard, this work aims to evaluate the evolution of the physical and biochemical quality of blueberries stored at -۲۰°C for three months. The results showed that one month of frozen storage increased the anthocyanins content in blueberries and preserved all other characteristics. Throughout the second month, the biochemical fruit quality improved, while the titratable acidity, pH, total soluble solids, and weight remained preserved. However, at the end of the storage duration, there was a continual rise in anthocyanins, and flavonoids, while polyphenols and antioxidant activity remained stable, surpassing the levels found in fresh blueberries. On the other hand, a notable decline in physical characteristics was observed. In this context, it is recommended to store blueberries at -۲۰°C for a maximum of one month for consumption in a fresh state. On the other hand, blueberries stored for more than two months must be intended for processed blueberry-based products to fully utilize their richness in phenolic compounds and avoid issues related to their sour taste and reduced weight.

کلیدواژه ها:

Antioxidant activity ، Blueberry ، Bioactive compounds ، Quality preservation ، Storage at -۲۰oC ، Shelf-life extension