High-voltage pulsed electric field laboratory device with asymmetric voltage multiplier for marine macroalgae electroporation. (March 2020)

• Record Type: Journal Article
• Authors: Levkov, Klimentiy; Linzon, Yoav; Mercadal, Borja; Ivorra, Antoni; González, César Antonio; Golberg, Alexander
• Is Part Of: Innovative food science & emerging technologies. Volume 60(2020)
• Publication Date: 2020-03
• Subjects: PEF pulse electric field -- CPE constant phase element -- ω frequency (in rads/s) -- j imaginary number -- Z impedance -- R∞ sample impedance at infinite frequency -- R0 sample impedance at zero frequency -- τ the characteristic time constant of the sample -- α a dimensionless parameter with a theoretical value between 0 and 1 -- Q0 the capacitance value of the seaweed in the chamber -- ESC energy storage capacitor -- EPC electroporation cell -- UESC voltage on the storage capacitor -- RCL the resistance to charge current -- CESC capacity of the energy storage capacitor -- Um value of the maximum doubled voltage -- CCL capacitance of the charging capacitor -- GPED gravitational press-electrode device; Pulsed electric field generator -- Electroporation -- Biomass processing -- Macroalgae -- Bioimpedance -- Bioeconomy; Food -- Biotechnology -- Periodicals; Food industry and trade -- Technological innovations -- Periodicals; Aliments -- Biotechnologie -- Périodiques; Food -- Biotechnology; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.ifset.2020.102288
• Languages: English
• ISSNs: 1466-8564

Abstract

Abstract: Optimization of protocols is required for each specific type of biomass processed by electroporation of the cell membrane with high voltage pulsed electric fields (PEF). Such optimization requires convenient and adaptable laboratory systems, which will enable determination of both electrical and mechanical parameters for successful electroporation and fractionation. In this work, we report on a laboratory PEF system consisting of a high voltage generator with a novel asymmetric voltage multiplying architecture and a treatment chamber with sliding electrodes. The system allows applying pulses of up to 4 kV and 1 kA with a pulse duration between 1 μs and 100 μs. The allowable energy dissipated per pulse on electroporated biomass is determined by the conditions for cooling the biomass in the electroporation cell. The device was tested on highly conductive green macroalgae from Ulva sp., a promising but challenging feedstock for the biorefinery. Successful electroporation was confirmed with bioimpedance measurements. Industrial relevance: Seaweed biomass is an emerging feedstock for biorefineries with already 30 million tons per year of global industrial production. However, most of the biomass produced today is lost. Pulsed electric field (PEF) extraction could allow saving energy on biomass drying, deashing and it could allow extracting various organic compounds. However, the parameters needed to seaweed biomass treatment with PEF are not known and will differ from species to species. Furthermore, very high salt content challenges most of the available laboratory PEF devices, limiting the ability for parameters optimization in the lab. The developed laboratory scale PEF system coupled to bioimpedance measurement provides a necessary set of tools and methods for PEF parameters optimization required for process scale-up. Highlights: Pulsed electric field generator with gravitation press electrodes was developed for seaweed biomass electroporation. Asymmetric voltage multiplying architecture allows to control the voltage of each pulse. PEF parameters 4 kV, 1 kA, 1–100 μs duration and total power dissipation of 20 W Macroalgae Ulva sp. was treated with 124 ± 12 V mm − 1, pulse duration 50 μs, pulse number 50, frequency 3 Hz. Electroporation of the biomass was confirmed with bioimpedance measurements.