The plantain starch was modified with octenylsuccinic anhydride (OSA) and spray and convection dried. The degree of substitution (DS), the sorption and thermodynamic characteristics were evaluated. The drying process affected the DS (0.009 and 0.015 to spray and convection drying, respectively). The monolayer moisture content was 7.46–9.01 and 7.33–8.04 g H2O 100 g−1 (db) to convection and spray dried OSA-plantain starch, respectively. The isokinetic temperature was ∼255 K, less than harmonic temperature (308 K), indicating that the water adsorption was entropy driven. The free energy showed that adsorption process was spontaneous. The shelf life of convection and spray dried OSA-starch was 434–1566 days to PET/FOIL/PE and 64–616 days to polypropylene packing. Thermodynamic differences in the adsorption process of OSA-plantain starch influenced by the drying method were not found. Spray-drying process could be used for the OSA-plantain starch production without altered the thermodynamic and transport properties of the amphiphilic material.