Pulsed electric field combined with preheating to preserve mildly extracted pea protein

Innovative extraction methods involving dry fractionation and aqueous phase separation have been recently developed to obtain plant-based protein ingredients with high texturing functionality. Such a process was applied to yellow peas, and the microbial quality of the extract was assessed. Pseudomonas trivalis and Erwinia gerundensis were identified as critical microbial contaminants due to their high growth capacities (at 10 °C). As a preservation strategy, pulsed electric field (PEF) treatment (24 kV/cm, 50 Hz, 126 μs) was employed, combined with different product inlet temperatures (25–45 °C). Ohmic heating (Δ T = 20 °C) was measured. At 25–30 °C, the microbial reduction reached 3 logs, attributed solely to electrical effects. At 40 °C, the reduction exceeded 4 logs, where thermal effects dominated. Further increase to 45 °C resulted in thermal modification of pea proteins, potentially compromising its gelling capacity. Additionally, the growth of PEF-treated contaminants at 5 and 10 °C were monitored, revealing rapid cell adaptation and proliferation. Finally, the extracts native microbiota showed an extension of the lag phase (4 days at 5 °C) after PEF treatment, accompanied by a pH stability of 10 days. The findings indicate improved microbial stability of the pea extract following PEF treatment. • P. trivalis and E. gerundensis are critical contaminants in pea extract. • Both species exhibited similar thermal and pulsed electric field sensitivities. • Pulsed electric field achieved 3 log reductions at temperatures below 50 °C. • Added thermal effects resulted in microbial reduction exceeding 4 log reductions. • Pulsed electric field extended the lag phase of the native microbiota of pea.