Pulsed electric field pretreatment to enhance sodium chloride and moisture diffusion in radish tissues while maintaining microstructural integrity

This study examined the influence of pulsed electric field (PEF) pretreatment on sodium chloride (NaCl) and moisture mass transfer in radish (Raphanus sativus L.) tissues, aiming to improve salting efficiency while preserving microstructural integrity. PEF was applied with 50, 75, and 150 pulses at a constant field strength (1.0 kV/cm), pulse width (20 μs), and frequency (50 Hz). Cell membrane disintegration index (Z-index) increased from 0.00 to 0.85 with pulse number, indicating progressive electroporation of radish tissue. NaCl and moisture diffusion were modelled using Peleg, Azuara, and Crank equations, with Azuara’s model providing the best fit (R ²=0.713–0.997; RMSE=0.000–0.011), especially under isotonic and hypertonic conditions. Diffusion rate constants (s¹ and D^e) correlated positively with pulse number, confirming that higher PEF intensities accelerated solute transfer. PEF-pretreated samples exhibited greater NaCl uptake and moisture retention under hypertonic conditions, while maintaining mechanical stability. PEF-pretreated samples retained their cutting force after salting (p>.05), whereas controls exhibited significant softening (p<.05). They also showed reduced volume shrinkage (p<.01), reflecting preservation of microstructural integrity. These results demonstrate the potential of PEF as a nonthermal technique to enhance salting performance and maintain quality in plant-based food products.