A study on the release kinetics and mechanisms of vanillin incorporated in almond gum/polyvinyl alcohol composite nanofibers in different aqueous food simulants and simulated saliva

Vanillin incorporated almond gum/polyvinyl alcohol (PVA) composite nanofibers were prepared using electrospinning. The release mechanisms and kinetics of incorporated vanillin were evaluated in different aqueous food simulants (distilled water, 10% ethanol, 50% ethanol and 3% acetic acid) and simulated saliva. Vanillin content in different media was determined by high‐performance liquid chromatography (HPLC). Vanillin release data were fitted to first order, Kopcha, Korsmeyer‐Peppas and Peppas‐Sahlin models to evaluate release mechanisms and kinetics. Release kinetics of vanillin in all mentioned media followed a pseudo‐Fickian diffusion mechanism. The vanillin release data in distilled water, 10% ethanol, 50% ethanol and simulated saliva fitted well to Peppas‐Sahlin model with regression coefficients 0.9937, 0.9936 and 0.9912, 0.9903, respectively. The release kinetics of vanillin in 3% acetic acid fitted to the Korsmeyer‐Peppas model with regression coefficient 0.9661. The release study in different aqueous food simulants showed burst release of vanillin within the first 5 min, followed by sustained release for 180 min. Nanofibers showed relatively good stability under dry ambient condition and maintained around 58 percentage of the incorporated vanillin for 90 days.