Development of active poly(butylene adipate‐co‐terephthalate) films incorporated with sodium benzoate and its application in white mushroom ( Agaricus bisporus ) packaging

The poly(butylene adipate-co-terephthalate) (PBAT) active films added with different concentrations (0%, 1%, 3%, 5%) of sodium benzoate (SB) were developed and their properties were evaluated. The FTIR analysis showed the interaction between PBAT and SB. The scanning electron microscope result exhibited that SB was uniformly dispersed in the PBAT matrix and tended to aggregate with its increasing content. The crystallinity of PBAT films increased for the incorporation of SB and it reached maximum for the film containing 3% SB. The color difference among all films was small, but the transparence decreased as SB increased. As the content of SB increased, the tensile strength (TS) and elongation at break (EAB) of films both increased first and then decreased, the film added with 1% SB possessed the maximum of TS and EAB. The gas barrier performance (oxygen and water vapor) of the films reduced with the increasing content of SB. Moreover, the results of the preservation of white mushrooms packaged by these films showed that the PBAT films added with SB could retard the browning, weight loss, soften, and the increase of microbiology of white mushrooms during storage. And the quality maintenance effect increased with the increasing content of SB. The results indicated that the active PBAT films added with SB were the potential to be used for food preservation. Practical applications Poly(butylene adipate-co-terephthalate) (PBAT) as one of biodegradable materials is considered a promising packaging material due to its biodegradability, high-temperature resistance, and high elongation at break. In this study, sodium benzoate acted as both nucleating agent and active agent was blended with PBAT to develop biodegradable active film. It evidenced that PBAT films containing different concentrations of SB were beneficial for the preservation of white mushrooms, which could delay the browning, weight loss, soften, and microbe growth of white mushrooms for 15 days. It also indicated that the PBAT films incorporated with SB could be potential to be used as antimicrobial active packaging for food preservation to extend its shelf life.