Effect of static magnetic field assisted freezing on the product quality of Korla fragrant pear

Freezing is a good method of preserving the sensory and nutritional quality of fresh fruits and vegetables. However, big ice crystals always form in a common freezing process which causes mechanical damage to the fruit and vegetable cells and results in low-quality products. The external magnetic field can interfere with the state of the internal water, thus changing the ice crystal formation process accordingly. It was suggested that suitable magnetic field treatments can affect the biological characteristics of fruits and vegetables and improve the quality of the frozen products. In this experiment, Korla fragrant pear was freezing processed at the different static magnetic field (SMF) strengths (0, 2, 4, 6, 8, and 10 mT), and the pear quality was evaluated by juice loss, color, texture, total soluble solid content and total acid content, water state, and distribution. The results showed that the utilization of SMF in freezing reduced the loss of juice and soluble solids, and maintained the titratable acidity. However, SMFs performed poorly in color and texture protection. This research suggested that magnetic field-assisted freezing had some positive effects on the quality of frozen Korla fragrant pear, but more works need to be done to further improve the product quality.Practical applications: This research emphasizes the positive effect of static magnetic field treatment on improving the freezing rate and optimizing the freezing process of Korla fragrant pear, which also provides a new idea and practical reference for the potential application of static magnetic field in freezing preservation of fruits and vegetables.