Abstract: To investigate the inclusion of essential oils in packaging materials, and improve its effective utilization rate, carvacrol were selected as the essential oil model, and halloysite nanotube-carvacrol composites were prepared by encapsulating carvacrol in halite nanotubes etched with 4 mol/L HCl, using a vacuum process. The controlled release system was prepared by polyelectrolyte encapsulation. The structure and morphology of halloysite nanotube etched with 4 mol/L hydrochloric acids, the carvacrol load and the release rate of carvacrol were characterized by using fully automatic surface and porosity analyzer, transmission electron microscope, Fourier infrared spectrometer and thermogravimetric analyzer stability. The results showed that the specific surface area of halloysite nanotube increased from 29.506 m2/g to 95.577 m2/g, and a load of carvacrol increased from 6.7% to 24.2%. Using polyelectrolyte encapsulation, the releasing of carvacrol in the composites was decreased significantly, and it had an obvious controlled-release effect. These results provided the basis for the application of essential oil as antibacterial and antioxidant food packaging materials.
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