Schematic illustration and SEM micrographs of immobilization methods of bromelain: (a) entrapment into hydrogels (Reproduced with permission from [86], Elsevier, Amsterdam, The Netherlands, 2018); (b) adsorption onto chitosan matrix (Reproduced with permission from [70], Elsevier, Amsterdam, The Netherlands, 2021); (c) covalent immobilization (Reproduced with permission from [81], Elsevier, Amsterdam, The Netherlands, 2018); (d) entrapment into nanoparticles (Reproduced with permission from [29], Elsevier, Amsterdam, The Netherlands, 2021); (e) SEM micrographs of encapsulated silica nanoparticles formed without bromelain (left) and with bromelain (right) (Reproduced with permission from [72], John Wiley and Sons, Hoboken, NJ, USA, 2014).