A polymeric chlorine dioxide self-releasing sheet to prolong postharvest life of cherry tomatoes

Chlorine dioxide (ClO2) as an effective sanitizer is widely used in postharvest handling. Because of its generation challenge such as equipment requirement for on-site production and ClO2 generator, application of ClO2 gas in retail is not currently feasible. In this study, a novel polymeric ClO2 self-releasing sheet was prepared using solution casting method. As such, sodium chlorite (NaClO2) can react with the citric acid in the polymer matrix in the presence of moisture. Poly (ether-block-amide) as the backbone of sheet was utilized to provide a hydrophilic system and generate of ClO2 gas. In addition, polyvinyl alcohol was used as a barrier layer to control the releasing level and increase the hydrophilicity. The new developed self-releasing sheet released sufficient ClO2 concentration to inactivate microbial growth and maintain the quality of cherry tomatoes during actual storage test. Overall, the self-releasing sheet containing lower content of NaClO2 exhibited better postharvest parameters. The new developed ClO2 self-releasing sheet is not just limited to postharvest handling and cherry tomatoes; it could also be used for wider applications such as medical sterilization or industrial sanitization.