Effects of extremely low frequency electromagnetic field at 50 Hz on myofibrillar protein from grass carp ( Ctenopharyngodon idellus ) during chilled storage at 4 °C

Biological interaction with extremely low-frequency electromagnetic fields (ELF-EMF) is complex and the 50 and 60 Hz frequencies are among a few ‘window’ frequency ranges reported with a stimulating effect. In the current study, ELF-EMF at frequencies from 40 to 70 Hz were examined for their possible significance in inducing biological effects during chilled storage of grass carp ( Ctenopharyngodon idellus ) at 4 °C for 4 and 6 h. The myofibrillar protein extracted from the grass carp was analyzed and the results indicate significant (p < 0.05) increases in Ca 2+ ATPase activity and pH, and a reduction in the total sulfhydryl content during the treatment of 50 and 60 Hz frequencies for both storage durations, in particular, the treatment of 50 Hz had pronounced effects with higher correlations. Therefore, the 50 Hz might be associated with the ‘window’ effect, enhancing myofibrillar protein quality during chilled storage.