Advances in Innovative Processing Technologies on Plant Materials: Understanding Structure-Process Interactions

The demand for fresh-like, high-quality plant-based foods has driven the development of innovative non-thermal processing technologies to enhance key processing steps. Among these technologies, pulsed electric fields (PEF) and high-pressure processing (HPP) are applied to different plant-based food matrices for quality preservation. This PhD thesis investigates the effects of PEF and HPP on the structural, textural, and physicochemical properties of different plant matrices, with a focus on structure-process interactions. Several fruits and vegetables, including mango, bell pepper, pumpkin, kiwi, and forced endive roots, were studied under controlled processing conditions. A multidisciplinary approach combining microstructural analysis, texture measurements, and compositional evaluation was used to assess how processing intensity influences cell integrity, tissue softening or reinforcement, peeling ability, and mass transfer phenomena. The results demonstrate that PEF induces intensity-dependent responses, with mild treatments preserving or enhancing firmness and improving peelability and mass transfer at low specific energy, while higher intensities promote tissue softening through extensive structural disruption. In contrast, HPP primarily affected firmness, colour stability, and microstructural integrity through pressure-induced cell wall and middle lamella modifications. Therefore, this work provides mechanistic insights that support the optimisation of non-thermal technologies for industrial applications aimed at improving the quality and functionality of fruit- and vegetable-based products.