Moderate pulsed electric field-induced structural unfolding ameliorated the gelling properties of porcine muscle myofibrillar protein

Pulsed electric field (PEF), as a promising non-thermal technology, has demonstrated its potential in improving the quality characteristics of meat products. To give an in-depth insight, the effects of PEF with varied electric field intensity (0-7.5 kV/cm) and treatment time (0-90 s) (equivalent to 0.76 x 103-5.32 x 103 kJ/kg energy input) on the conformation and gelling properties of vital myofibrillar protein (MP) were evaluated. With the augmenting pulse intensity and time, alpha-helix of MP decremented with a coinstantaneous increase of fl-sheet, fl-turn, and random coil. Upon PEF treatment, the surface hydrophobicity increased extensively (up to 46%) whereas total sulfhydryls endured a massive loss, contributing to the enhancement of hydrophobic interactions and disulfide bonds. Consequently, more fine-stranded strong gels with transcendent elasticity and water holding capacity (WHC) were generated. However, when the output of PEF exceeded a pivotal level (intensity >7.5 kV/ cm, time > 60 s), the alpha-helix content was increased, and the surface hydrophobicity decreased remarkably (P < 0.05), possibly due to protein aggregation. The undue PEF treatment resulted in the deterioration of MP gel strength and WHC. Additionally, PEF caused no visible changes in the SDS-PAGE pattern under the tested PEF levels.

Automated summary

Pulsed electric field (PEF) has the potential to improve the quality characteristics of meat products by altering the conformation and gelling properties of proteins. Increasing the pulse intensity and time enhances hydrophobicity, elasticity, and water holding capacity (WHC), leading to stronger and more stable gels. However, excessive PEF treatment may result in protein aggregation, diminishing gel strength and WHC.