Enhanced Extraction from Solid Foods and Biosuspensions by Pulsed Electrical Energy

The purpose of this article is to review matters dealing with application of electrical pulsed energy (pulsed electric field, pulsed ohmic heating and high voltage electrical discharges) for enhancing the solid-liquid extraction in the food industry. The quality of products (e. g., purity, color, texture, flavor and nutritients) extracted from solid foods (sugar beets, apples, grapes, etc.) and quality of proteins and polysaccharides extracted from biosuspensions (aqueous suspensions of yeast, e. coli cells, etc.) may be degraded by conventional mechanical, thermal or chemical pretreatment. The traditional treatments are restricted by temperature elevation and require high energy consumptions; moreover, chemical methods are based on application of unsafe organic solvents, enzymes and detergents. Physical treatments assisted by electrical pulsed energy are shown to be very remarkable for enhancing the solvent and pressure extraction and dehydration processes and of high interest for the food industry. This article provides an overview of the pulsed energy extraction technologies showing promise for commercial food processing.