Fresh pork begins to deteriorate almost immediately after slaughter as muscle tissue consumes its remaining energy reserves. A recent study published in Food Quality and Safety (DOI: 10.1093/fqsafe/fyag047) demonstrates that applying an electrostatic field (EF) during near-freezing storage can significantly slow this process at the biochemical level.
The research, conducted by scientists from the Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, and the College of Food Science and Engineering, Ocean University of China, examined pork muscle stored under three conditions: conventional refrigeration at 4 ± 0.5 °C, controlled freezing-point storage at −1 ± 0.5 °C, and the same near-freezing conditions with a continuous 12-kilovolt EF. The team tracked metabolic changes from 1.5 to 120 hours postmortem, focusing on energy metabolites, glycolytic enzymes, and sarcoplasmic protein structure.
Results showed that after 120 hours, EF-treated pork contained 17.5% less lactate than conventionally refrigerated samples. Glycogen and ATP consumption were reduced by approximately 14.9% and 37.3%, respectively, while pyruvate retention was higher. The treatment also lowered Na⁺/K⁺-ATPase activity, indicating altered energy metabolism. Early exposure to EF promoted larger protein aggregates, but from 36 to 120 hours, proteins became smaller, more dispersed, and structurally ordered. Enzyme modifications shifted over time, with the EF treatment generally reducing phosphorylation and increasing acetylation of key glycolytic enzymes—lactate dehydrogenase (LDH), triosephosphate isomerase (TPI), and pyruvate kinase (PK)—consistent with slowed glycolytic activity.
This research is significant because it reveals that the preservation effect is not merely due to lower temperatures. Instead, the EF appears to alter the molecular environment in which glycolytic enzymes operate, affecting both protein conformation and post-translational modifications (PTMs) that regulate enzyme activity. The time-dependent response—initial protein unfolding and aggregation followed by dispersion and ordering—offers a mechanistic explanation for the slower conversion of pyruvate to lactate and better retention of cellular energy during storage.
These findings provide a foundation for developing electrostatic-field-assisted cold storage for fresh meat supply chains. By slowing pH decline and conserving ATP, the technology may help protect water-holding capacity, texture, appearance, and marketable quality during processing, transport, and retail display. The low-power 30-watt system also suggests potential for energy-efficient preservation, though commercial benefits were not directly tested in this experiment.
Future research should validate the proposed causal link between protein structural changes and enzyme PTMs, potentially through molecular dynamics simulations. Larger studies are needed to assess microbial safety, sensory quality, shelf life, equipment scalability, temperature fluctuations, operating costs, and performance across different muscles and meat products before industrial adoption.
