Impact of Low-Frequency Alternating Electromagnetic Fields on Postharvest Preservation of Satsuma Mandarins

Low-frequency alternating electromagnetic fields (LF-AEMF) represent an innovative processing technology with significant potential for extending the shelf life of fruits and vegetables by modulating key physiological processes. In this study, the impact of the LF-AEMF intensities (1300, 1800, and 2500 V) on the postharvest preservation of satsuma mandarins was evaluated. Compared to the control group, the LF-AEMF-treated samples exhibited reduced weight loss (0.62% vs. 2.11%), respiration rate (32.73 vs. 40.08 mg/kg·h), and malondialdehyde (MDA) content (40.80 vs. 34.87 nmol/g) after 40 days of storage. In addition, LF-AEMF treatment also effectively preserved titratable acidity (TA) (0.34% vs. 0.30%), vitamin C (Vc) content (7.77 vs. 7.05 g/100 g), and phenylalanine ammonia-lyase (PAL) activity (79.757 vs. 62.395 U/g). E-nose analysis and low-field NMR further revealed that the application of LF-AEMF effectively facilitated the superior preservation of the intrinsic flavor profile of the satsuma mandarins and mitigated the loss of free water within the fruit. Overall, this research provides valuable insights for the potential application of LF-AEMF in extending the storage life of citrus fruits, which may also be applicable to other seasonal fruits and vegetables that require long-term storage.