Application of clay-TiO2 nanocomposite packaging films on pears (Prunus communis L. cv. Williams) under cold storage

Today, nanomaterials are presenting novel characteristics can be applied in developing new packaging with modified preferred properties. These are including the development of packaging with improved barrier characteristics which will extend the storage life of a product. In the present study, the effect of three types of developed low-density polyethylene nanocomposite films with two types of TiO2 (anatase and rutile) and clay (Closite 20A) nanoparticles were evaluated on the quality parameters of pear fruit (cv. 'Williams') during 48 days of storage at 4 degrees C. The Mechanical test revealed that the reinforcement in the presence of the nanocomposites was more than that with their conventional counterparts. The barrier properties against oxygen, carbon dioxide and water vapor of nanocomposite films were significantly decreased. The results showed that nanocomposite packaging film (NPFs) was a promising oxygen, carbon dioxide and water vapor barrier. Weight loss, firmness and the total solids content of pear in clay/TiO2-nanocomposite film decreased at the rates of 50%, 39% and 13%, respectively due to the modified atmosphere. Higher ascorbic acid content, lower ethylene production, reducing sugar content and PPO activity and higher POD of the packed fruits were observed in clay/TiO2-nanocomposite film. The single use of clay and TiO2 nanoparticles was not as effective as both of them in increasing durability of pear fruits. So, clay/TiO2-nanocomposite film can be considered as a practical approach to reduce the risk of pathogens, contamination and to improve the maintenance quality of pear fruit during the storage.