Plasmolysis of sugarbeet: Pulsed electric fields and thermal treatment

Selective Extraction from Food Plants and Residues by Pulsed Electric Field

“…Solute diffusivities inside sugar beet tissue were nearly the same for sugar diffusion from untreated tissue at 60 ∘ C and from PEF-pretreated tissue at 30 ∘ C. The purest juice was obtained after cold diffusion. However, juice purity was higher for slices pretreated by PEF than for untreated slices even after thermal diffusion at 70 ∘ C [30].…”

“…Better conservation of the tissue structure under cold conditions during electrical treatment would allow more pectins to remain in the cellular matrix. Recently, PEF-assisted pressing and aqueous extraction from sugar beets were intensively studied on the laboratory scale [18][19][20][21][22][23][24][25][26][27][28][29][30][31]. Different aspects were investigated, and it was shown that up to 82% of the overall yield could be achieved by two-stage pressing with an intermediate PEF application.…”

Mass Transfer Enhancement by Means of Electroporation

“…Fig. 9b shows the Arrhenius plots of the effective sugar diffusion coefficient D eff of PEF treated sugar beets from two independent experiments (Lebovka et al, 2007a;El-Belghiti et al, 2005). For example, PEF treatment conducted at E=0.1 kV/cm and t PEF = 1 s caused the reduction of the activation energy from ≈ 75 kJ/mol (untreated sample) to ≈ 21 kJ/mol, with the D eff values being always larger for PEF treated samples (Lebovka et al, 2007a).…”

“…9b shows the Arrhenius plots of the effective sugar diffusion coefficient D eff of PEF treated sugar beets from two independent experiments (Lebovka et al, 2007a;El-Belghiti et al, 2005). For example, PEF treatment conducted at E=0.1 kV/cm and t PEF = 1 s caused the reduction of the activation energy from ≈ 75 kJ/mol (untreated sample) to ≈ 21 kJ/mol, with the D eff values being always larger for PEF treated samples (Lebovka et al, 2007a). Interestingly, a different experiment resulted in similar values of the activation energy (≈ 21 kJ/mol) of D eff for sugar extraction from sugar beet after a PEF treatment conducted at E = 0.7 kV/cm and t PEF = 0.1 s. Similarly, the values of the effective diffusion coefficient D eff , estimated for extraction of soluble matter from chicory, were significantly higher for PEF-treated samples (E = 0.6 kV/cm and t PEF = 1 s) than for untreated samples in the low temperatures range, while at high temperature (60 -80 °C) high D eff values were observed for both untreated and PEF-pretreated samples.…”

“…(b) Diffusion of sugar from sugar beets. PEF treatment conditions were E=0.1 kV/cm and t PEF = 1 s (Lebovka et al, 2007a) and E=0.7 kV/cm and t PEF = 0.1 s (ElBelghiti et al, 2005).…”