Exploiting films based on pectin extracted from yellow mombin (Spondias mombin L.) peel for active food packaging

Abstract

In this study, the potential of yellow mombin (Spondias mombin L.)–extracted pectin as a film-forming matrix for the elaboration of edible coatings was investigated. The films of chitosan, citric pectin, and carboxymethylcellulose (Sigma/USA) and natural pectin were prepared by casting. The film morphological characterization was performed by scanning electron microscopy (SME), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and atomic force microscopy (AFM). Additionally, total phenolic compounds (TPC), total antioxidant activity (TAC), DPPH scavenging capacity, and antimicrobial activity were assayed for the natural pectin–based films. The results showed that the film based on natural pectin presented a 46% degree of esterification that was higher than commercial (34%), showing its capacity of forming gels. The film formed by chitosan presented a very different behavior for loss of mass during TGA when compared to the other films, occurring a mass loss completely at 647.7 °C in 61 min. The value obtained from the concentration of total phenolics (mg GAE/100 g dried) found in the formulated film based on pectin was 3998.99 ± 42.64 and with solubility in water of almost 100%. Additionally, the scavenging of the DPPH radical with a value of 15.48 ± 1.48 μmol TE/g was found on the film based on natural pectin thus showing antioxidant capacity. Finally, this film showed less significant mechanical properties when compared to other films and a good pronounced antimicrobial effect against the gram-negative bacteria tested. Therefore, it could be potentially used for producing food-active packages.