Pulsed electric field processing of forced endive roots: Enhanced extraction and pilot-scale validation

Forced endive roots (Cichorium intybus L.), usually discarded after forcing, represent a valuable biomass rich in carbohydrates and bioactive molecules. This study investigated the use of Pulsed Electric Field (PEF) treatment to enhance the diffusion of intracellular solutes from forced endive root tissues and to support the development of a scalable extraction process. Roots were treated at different PEF intensities (2.98–142.4 kJ/kg), and soluble-matter diffusion was evaluated at 20 °C and 70 °C. PEF significantly accelerated solute release compared with untreated samples, with 28.44 kJ/kg and 142.4 kJ/kg intensities achieving the highest °Brix values at both temperatures despite their markedly different cell disintegration levels. Based on diffusion performance, energy efficiency, and structural responses, 28.44 kJ/kg intensity level was selected for upscaling. Pilot-scale experiments (diffusion at ambient temperature) confirmed the laboratory trends, with the upscaled PEF treatment matching the diffusion kinetics of the selected laboratory condition and yielding a 2.47-fold increase in soluble sugars compared with untreated samples. Textural analyses showed that PEF treatment induced significant tissue softening, consistent with electroporation-driven structural weakening, while maintaining tissue integrity better than freeze-thawing. In conclusion, PEF demonstrated strong potential as an energy-efficient, scalable technology for the carbohydrate-oriented valorization and fermentation-based applications.