Effects of magnetic field-assisted thawing on the physicochemical properties of blueberries.

BACKGROUND

Thawing is the central step in frozen berry processing, and it directly determines the final quality of the product. Conventional thawing is slow and has a negative impact on quality. Magnetic field application has lately been used in thawing. This study aimed to explore the impact of magnetic fields on the thawing time, water distribution, physicochemical properties, and microstructure of blueberries and to compare the results with those of air thawing (AT) and water immersion thawing (WT).

RESULTS

Magnetic field-assisted air thawing (MAT) and magnetic field-assisted water immersion thawing (MWT) reduced the thawing time by 15% and 34%, respectively, while reducing drip loss by 16% and 28%, respectively. Additionally, magnetic field-assisted thawing effectively preserved essential nutrients and prevented the increase in polyphenol oxidases and peroxidases. Confocal laser scanning microscopy revealed that MWT better preserved the cellular structure of blueberries.

CONCLUSIONS

Magnetic field-assisted thawing can shorten thawing times, reduce ice crystal damage to cells, and better maintain the quality of blueberries. This study proposes a new blueberry thawing method with high application prospects. © 2025 Society of Chemical Industry.