Impact of pulsed electric field pretreatment on protein and its binding with sodium ions in brined beef

This study investigates the effects of pulsed electric field (PEF) pretreatment on the protein properties of a beef matrix following brining, specifically focusing on the interaction between Na⁺ ions and proteins. We examined the impact of PEF pretreatment at varying field strengths (2, 3, and 4 kV/cm) for 60 s on NaCl diffusion and the secondary and tertiary structures of proteins in beef samples brined for 150 min. Results indicated that the highest NaCl content of 2.65 % (4 kV/cm) was considerably greater than the 2.32 % observed in the control group. PEF pretreatment altered the interaction between Na⁺ ions and proteins, enhancing the mobility of Na⁺. While the effects of PEF on protein composition and denaturation were insignificant, an increase in field strength resulted in a significant rise in β-sheet content and a corresponding decrease in random coil content (P < 0.05). Additionally, the increase in surface hydrophobicity and decrease in fluorescence intensity suggested that PEF pretreatment led to protein unfolding and an increase in the thermal denaturation temperature of the meat. Furthermore, the PEF-pretreated samples exhibited a tighter protein gel network during temperature sweeps and improved springiness. In conclusion, PEF pretreatment altered the protein structure and enhanced Na⁺ mobility in meat.