Evaluation of Potato Tissue Hydration and PEF Response Through Low‑Voltage Electrical Monitoring

INTRODUCTION: PEF is an emerging technology used in the food industry as a pre‑treatment that promotes cell membrane permeabilization. It is often used to improve the nutritional and sensory quality and microbial inactivation. Water soaking and other pre‑treatments can lower acrylamide and alter texture, crispness, and oil uptake in fried potatoes. In fried potato processing, PEF has been used as an alternative or complementary non‑thermal pre‑treatment to conventional thermal steps such as blanching. However, there are few studies addressing the effect of potato immersion time in water and its implications for subsequent PEF application. This work aims to investigate the effect of water immersion time on potato tissue and to propose a preliminary low‑voltage electrical sensing step to assess tissue viability for PEF. METHODS: The samples were divided into four experimental groups: untreated (UT), water immersion (WI), PEF treatment (PEF), and water immersion followed by PEF (WIPEF). The experiments were carried out at different immersion times (5, 10, 15, 30, and 60 minutes). PEF treatment was performed under controlled conditions, using 50 pulses of 100 µs duration and an electric field intensity of 1.5 kV/cm. System electrical parameters: voltage, current, and conductivity were monitored in order to evaluate changes associated with the tissue’s structural state. RESULTS: The measurement of the electrical parameters has potential to indicate changes in ion leaching and conductivity caused by the pre‑treatments. Current and conductivity measurements allow to characterize the structural state of the potato, indicating its level of cellular permeabilization prior to PEF application. CONCLUSIONS: The inclusion of a low‑voltage electrical sensing step, based on impedance measurement and associated with immersion time, shows potential to assist in process control and automation. This approach makes it possible to evaluate whether the tissue is ready to proceed to PEF treatment.