Plasmolysis of sugarbeet : Pulsed electric fields and thermal treatment

Abstract The influence of pulsed electric fields (PEF) and heating on the cell damage (plasmolysis) of sugarbeet tissue was studied. The PEF treatment was applied using bipolar pulses of near-rectangular shape in near-isothermal regime. The thermal treatment temperature interval was within T = 20–70 °C. The tissue damage degree was characterized by the electrical conductivity disintegration index Z. The Arrhenius form of the characteristic damage time – temperature dependences was observed both for the electrical and thermal processes. The corresponding activation energies W ≈ 149–166 kJ mol−1 were responsible for the damage of cell membranes. The PEF treatment noticeably accelerates the diffusion process, which requires ≈1 h with mild heating at 40 °C. The results shown open new prospects for low heating processing in sugar industry.

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