Hydrodynamic Cavitation for Natural Macromolecule and Biopolymer Processing: A Comprehensive Review

Natural macromolecules and biopolymers are central components in biological, food, pharmaceutical, and materials systems. Pectins, polysaccharides, cellulose, lignin, chitin, chitosan, polyhydroxyalkanoates, proteins, and macromolecular complexes can be recovered from renewable matrices or modified to obtain specific technological functions. Hydrodynamic cavitation is assessed as an intensification platform for the recovery and processing of these fractions. Attention is directed to the relationship between process configuration, molecular structure, and final performance. Extraction yield alone is not considered sufficient to define the technological value of the treatment. Matrix disintegration, mass transfer, dispersion, emulsification, fibrillation, controlled depolymerization, and structural modification are considered. Reactor configuration, operating severity, fraction stability, molecular characterization, rheological properties, colloidal behavior, energy consumption, and scale-up transferability are also evaluated. The available evidence, including representative quantitative and functional descriptors reported in the literature, indicates that hydrodynamic cavitation should not be interpreted as a universally superior technology. Its relevance is stronger when a measurable, reproducible, and functionally meaningful advantage is demonstrated against appropriate controls and alternative technologies.