Electrostatic Fields Slow Pork Glycolysis During Near-Freezing Storage

Fresh pork begins to deteriorate almost immediately after slaughter as muscle tissue consumes its remaining energy reserves. Now, researchers have shown that combining an electrostatic field (EF) with controlled freezing-point storage can slow this process at the biochemical level, offering a potential new method for preserving 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 at -1°C, and the same near-freezing conditions with a continuous 12-kilovolt electrostatic field. The researchers tracked changes in energy metabolites, glycolytic enzymes, and sarcoplasmic protein structure over 120 hours postmortem.

The results showed that pork treated with the electrostatic field contained 17.5% less lactate than conventionally refrigerated samples after 120 hours, while glycogen and ATP consumption were reduced by 14.9% and 37.3%, respectively. The treated samples also retained more pyruvate and exhibited lower Na⁺/K⁺-ATPase activity, indicating a slower metabolic cascade that typically lowers pH and damages water retention.

One of the key findings was the effect on post-translational modifications (PTMs) of glycolytic enzymes. The electrostatic field tended to reduce phosphorylation and increase acetylation of enzymes like lactate dehydrogenase (LDH), triosephosphate isomerase (TPI), and pyruvate kinase (PK), which is consistent with slower glycolytic activity. This suggests that the preservation effect is not simply due to temperature but involves molecular changes in the enzyme environment.

The study also observed time-dependent changes in protein structure. Early exposure to the electrostatic field promoted larger protein aggregates, but from 36 to 120 hours, the proteins became smaller, more dispersed, and more ordered. This sequence may explain the reduced conversion of pyruvate into lactate and better retention of cellular energy during storage.

These findings provide a mechanistic foundation for developing electrostatic-field-assisted cold storage for fresh meat supply chains. By slowing pH decline and conserving ATP, the technology could help protect water-holding capacity, texture, appearance, and overall quality during processing, transport, and retail display. The low-power system (30 watts) 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, including molecular dynamics simulations. Larger studies are needed to 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.