Impact of pulse width and field strength variations in pulsed electric field-assisted freezing on hybrid giant tiger grouper fillets and freezing energy consumption

Abstract

Freezing is essential for the distribution of hybrid giant tiger grouper (Epinephelus fuscoguttatus & times; Epinephelus lanceolatus), but it often leads to quality deterioration and high energy consumption. In this study, simultaneous pulsed electric field (PEF)-assisted freezing was applied using different pulse widths and electric field strengths to improve freezing performance and product quality. Wide-pulse PEF significantly accelerated freezing, reducing freezing time by up to 55.4%. The shortened crystallization phase observed in freezing curves was accompanied by improved microstructural preservation in histological analysis. These changes resulted in lower drip loss and cooking loss, while maintaining texture properties comparable to fresh samples. According to results from twoway ANOVA analysis, pulse width exhibited a more pronounced effect on freezing performance compared with field strength. Lipid oxidation was not adversely affected, suggesting that corona-related oxidative effects were not evident under the tested conditions, while total volatile basic nitrogen levels were reduced. Furthermore, wide-pulse PEF treatment at 4.5 kV/cm significantly lowered overall energy consumption in a laboratory-scale system. These findings demonstrate the potential of simultaneous PEF-assisted freezing as an effective and sustainable approach for improving frozen seafood quality and energy efficiency.