Fabrication and characterization of a chitosan/cyclodextrin/TiO2-NPs composite for preservation of avocados

• Published in: RSC advances 2024-08, Vol.14 (35), p.25802-25810
• Main Authors: Thi Lan Pham, Nguyen, Manh B, Bui, Van Cuong, Nguyen, Thi Xuyen, Savitskaya, T A, Le-Deygen, Irina, Hoang Thai, Dai Lam Tran
• Format: Article
• Language: English
• Subjects: Antiinfectives and antibacterials; Chitosan; Coliforms; Cyclodextrins; E coli; Gram-positive bacteria; Mechanical properties; Nanoparticles; Polymer films; Relative humidity; Ripening; Tensile strength; Titanium dioxide; Water vapor; Weight loss
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d4ra04207g

In this study, a TiO2 material with nanoparticle size of about 10–20 nm, surface area of 109 m2 g−1 was synthesized using the microwave-assisted hydrothermal method. The chitosan/TiO2 film combined with cyclodextrin (chitosan–cyclodextrin/TiO2, CS–CD/TiO2NPs) helps significantly improve the mechanical properties and enhance the antibacterial activity of the polymer film. Furthermore, the content of TiO2 nanoparticles in CS–CD/TiO2NPs also affects the tensile strength, antibacterial activity, ripening rate, ethylene production rate, and water vapor permeability during food preservation of the CS–CD film that has been studied. The CS–CD/TiO2NPs film is effective against Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aereus) reaching over 99.5% after 15 min of contact. The preservation ability of avocados coated with CS–CD/TiO2NPs was evaluated through some physiological parameters of the avocados, such as sensory evaluation, weight loss, and hardness. The results show that the use of CS–CD/TiO2NPs films extends the preservation time of avocados up to 7 days under conditions of 30 °C and 80% relative humidity.