Pectin bioplastic films regenerated from dragon fruit peels

Abstract

Pectin extracted from dragon fruit peels was used to prepare pectin-based membranes by mixing with the plasticized agent polyethylene glycol (PEG) at pectin to PEG ratios of 5:1, 3:1, and 1:1. SEM images showed the resulting bioplastic films had a transparent yellowish surface without pores or cracks. The water content of the bioplastic films was 29.17, 48.61, and 59.72% for the 5:1, 3:1, and 1:1 ratios, respectively. This showed that the increase in PEG concentration made the bioplastic films weaker and more hydrophilic. The tensile strength of films was 5.0, 4.9, and 2.5 N/mm2 and the value of optical transmittance was 18, 19, and 24%, for the 5:1, 3:1, and 1:1 ratios, respectively. The significant decrease in tensile strength is attributed to the high concentration of PEG, which lead to the clustering in the material’s structure. Therefore, these bioplastic films are applicable to the highly suitable and stable operations of packing materials in the food and medical industries.