Sustainable Electroporator for Continuous Pasteurisation: Design and Performance Evaluation with Orange Juice

Abstract

Electroporation is a simple but effective and sustainable food processing way of treating cell membranes with an electric field. It is employed in a variety of ways in the food industry, ranging from shelf-life extension to green extraction. Despite its wide range of applications, electroporators are out of reach for many labs due to their high development costs, and different electroporators have been tailored to specific applications. The designing sequence of an electroporator that takes the geometry of a treatment chamber and its electrical resistance into account for the design of a pulse generator has not been addressed in published literature. To meet this demand, this study presents a straightforward way to develop a simple, affordable, and portable electroporator for liquid food pasteurisation. The proposed electroporator comprises a coaxial treatment chamber with static mixers and a high-voltage Marx bank based on insulated-gate bipolar transistors (IGBTs). The generator has a 4.5 kV output voltage and a peak current rating of 1 kA; however, the modular design allows for a wide range of voltage and current ratings. Treated orange juice using thermal pasteurisation (65 °C, 30 min) was also used for comparison. The performance of the electroporator was studied using chemical and microbial tests. A significant log reduction (5.4 CFU.mL−1) was observed in both the PEF-treated samples with sieves. Additionally, the treated juice visual and chemical color analysis showed that the PEF-treated sample extended the shelf-life after 9 days of storage at 4 °C. This research also examines the energy conversion in these two processing steps. This study assists in developing further electroporators for other food applications with different treatment chambers without compromising the product’s quality.

Optimized Alternating Current Electric Field and Light Irradiance for Caulerpa lentillifera Biomass Sustainability—An Innovative Approach for Potential Postharvest Applications

“…As preliminary reported, ACEF treatment at 125 kV/m for 60 min can inhibit the PQ deterioration of seagrape [1]. However, optimization is needed to obtain a more efficient and economical process [28]. Currently, there is a great emphasis on increasing seagrape quality using green technologies, such as ACEF, an interesting study.…”

“…For instance, the seagrape was treated with EF intensity of 50 kV/m for 30, 60, and 90 min, resulting in firmness of 0.0397, 0.0519, and 0.0387 N, respectively. This phenomenon might be due to the rise time becoming critical for charging and possible electroporation of the cell surface membrane because it is related to the intracellular membrane charging time and the limit of transmembrane voltage [28,38]. In this case, the seagrape tissue may still endure and reach its peak to interfere with its physicochemical properties from 30 to 60 min of treatment, but it becomes not effective anymore after reaching 90 min of treatment.…”

Effect of Non-Thermal Food Processing Techniques on Selected Packaging Materials

“…Economically, although expensive for industrial implementation, PEF technology is cost and time effective. About 50% less electricity is required when compared to low-temperature-low-time thermal treatment [ 17 , 18 ]. Unfortunately, main disadvantages of this processing are: (i) requirement of a high peak power, (ii) limited (rather low) volume of the liquid that can be treated, (iii) inevitable occurrence of electrochemical reactions between the electrode and the food such as electrolysis of water, corrosion and migration.…”