The Preparation Of Functional Nanofibers And Applications In The Field Of Active Packaging

The application of nanofiber film in the field of food active packaging has been widely studied in recent years.Fruit and vegetable were easy to be mildew and putrefied due to their vigorous tissue metabolism,microorganism activity and water loss,resulting in shortened shelf life.Natural green antibacterial agents and catalysts were added into the polymer solution,and the functionalized nanofiber film was obtained after blending by electrospinning technology.The application of nanofiber film in the field of active packaging of fruits and vegetables can better guarantee the quality and safety of food.In this paper,on the one hand,TiO₂ nanoparticles were co-blended into polyacrylonitrile?PAN?nanofibers as catalysts to prepare a composite nanofiber film for degradation of ethylene in the storage environment of fruits and vegetables.On the other hand,thymol was encapsulated into PLGA fibers as antibacterial agents and used as antibacterial packaging materials in the field of food preservation.The main content is as follows:?1?The study aimed to develop a nanofiber film for photocatalytic degradation of ethylene and slowing down the ripening of banana fruit.Nanofibers containing different amounts of TiO₂ nanoparticles?1 wt%,5 wt%,and 10 wt%?were prepared using electrospinning method.Nanofibers containing 5 wt%TiO₂ exhibited a nano-scale structure,good nanoparticle uniformity,and an anatase phase as characterized by scanning electron microscopy,energy dispersive X-ray spectrometer and transmission electron microscopy.Nanofibers containing 5 wt%TiO₂ were tested in a photocatalytic reactor and showed higher photocatalytic activity for the degradation of ethylene.The utility of the photocatalytic reaction was further confirmed via a banana fruit-ripening test.The TiO₂ nanofiber successfully delayed the color change and softening of bananas during storage.The results suggest that the TiO₂ nanofiber offers photocatalytic degradation of ethylene and could potentially be used as packaging material for delaying postharvest fruit ripening.?2?In the present work,thymol as an antibacterial agent was encapsulated into poly?lactide-co-glycolide?to form core-shell nanofibers by coaxial electrospinning.With such a core-shell nanofiber film,thymol can be slowly released to headspace between food and the nanofiber film,inhibiting the growth of bacteria on the surface of food.Through the morphology characterization of the prepared nanofibers,it can be clearly observed that the prepared nanofibers were core-shell structures.The antibacterial and fruit preservation abilities of the nanofiber film were tested on strawberries.Studies have shown that it can effectively extend the shelf life of strawberry.This novel antibacterial packaging material with excellent biodegradability and good sustained release performance would have a broad application prospect in the field of food preservation.