Aplicação de filme ativo adicionado de curcumina como embalagem antioxidante/antimicrobiana

Abstract

Active packages interact with food in order to increase its safety and shelf life. Curcumin is a compound that exhibits antioxidant and antimicrobial properties, being a potentially viable alternative to incorporate into active films. Thus the objective of this work was to evaluate the application of active package added with curcumin (0.5%wt with respect to the polymer) as packaging for an oil rich in polyunsaturated fatty acids (chia oil) and a meat product (hamburger). As a control, a package was produced with the same basic formulation, but no curcumin was added to it. The packagings were characterized in relation to their antimicrobial (disk diffusion against Escherichia coli, Pseudomonas aeruginosa and Staphylococus aureus) and antioxidants characteristics (DPPH and ABTS), as well as to their opacity (UV-Vis spectrophotometry). The results showed that curcumin remained stable even after being subjected to the high temperatures during the extrusion process, since the film showed significant high results in relation to its antioxidant capacity (DPPH of 1605.25 ± 48.13 and ABTS equal to 2815. 77 ± 15.25 μmolTrolox Equivalent/ 100gfilm) and antimicrobial activity (inhibition halo up to 0.85 cm). Films opacity results did not indicate significant differences between the curcumin added film and control formulation. In the stage of films application as active packages, chia oil´s oxidative stability during the storage in an oven at 60 °C for 7 days was investigated. UV-Vis spectra were obtained from the oil packed with control film, film added with curcumin and chia oil without packaging (control oil), and the technique of multivariate resolution of alternating least squares curves (MCR-ALS) was applied to evaluate the degradation products over the storage. The films were also applied to commercial hamburgers (composed by chicken and beef meat), being evaluated the packed products lipid oxidation by TBARS, microbial deterioration (mesophilic and psychotropic microorganisms) and pH during a period of seven days, in refrigerator. A control evaluation was performed keeping the hamburger in its own original packaging (where it is commercialized). The results showed that there was no significant difference between the hamburgers packaged with control film, film added with and original burger packaging for the microbiological, pH and TBARS analyzes. Thus, the film added with 0.5%wt curcumin was more effective in protecting chia oil against the formation of oxidation products, as well as against the degradation of tocopherol. However, in the application of the film in industrialized hamburgers the film added with curcumin showed a similar behavior of the original packaging, keeping the pH value and mesophilic bacteria within the limit acceptable for consumption.