Fresh pork begins to deteriorate almost immediately after slaughter as muscle tissue consumes its remaining energy reserves. Researchers have now demonstrated that applying an electrostatic field (EF) during controlled freezing-point storage can slow this process at the biochemical level, offering a potential new method for maintaining meat quality during refrigerated transport and storage.
The study, published in Food Quality and Safety (DOI: 10.1093/fqsafe/fyag047), examined pork muscle stored under three conditions: conventional refrigeration at 4°C, controlled freezing-point storage at −1°C, and the same near-freezing conditions with a continuous 12-kV electrostatic field. The researchers tracked changes in energy metabolites, glycolytic enzymes, and sarcoplasmic protein structure over 120 hours postmortem.
Results showed that the electrostatic field treatment retained more glycogen and adenosine triphosphate (ATP), limited lactate accumulation, and reduced the activity of sodium-potassium ATPase. Specifically, at 120 hours, treated pork had 17.5% less lactate than conventionally refrigerated samples, while glycogen and ATP consumption were reduced by 14.9% and 37.3%, respectively. The treatment also altered the structure of soluble muscle proteins, initially promoting larger aggregates but later leading to smaller, more dispersed, and more ordered proteins.
The study also examined post-translational modifications (PTMs) on key glycolytic enzymes: lactate dehydrogenase (LDH), triosephosphate isomerase (TPI), and pyruvate kinase (PK). The treatment tended to reduce phosphorylation and increase acetylation, consistent with slower glycolytic activity. Correlation analysis linked these enzyme modifications to the observed protein structural changes.
The authors suggest that the preservation effect is not solely due to lower temperature but involves the electrostatic field influencing the molecular environment of glycolytic enzymes, altering both protein conformation and the chemical switches that regulate enzyme activity. This time-dependent response provides a possible explanation for the slower conversion of pyruvate into lactate and better retention of cellular energy during storage.
These findings offer a mechanistic 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 saleable quality during processing, transport, and retail display. The low-power 30-watt system suggests potential for energy-conscious preservation, although commercial benefits were not directly tested.
Future research should validate the proposed causal link between protein structural changes and enzyme PTMs, including through molecular dynamics simulations. Larger studies should also assess microbial safety, sensory quality, shelf life, equipment scale-up, temperature fluctuations, operating costs, and performance across different muscles and meat products before industrial adoption.
