Filmes biopoliméricos à base de alginato de sódio e enriquecidos com líquido da casca da castanha de caju (LCC) para conservação de carne bovina.

Abstract

Films are thin layers of materials used in food, which aim to present considerable effects on their conservation, distribution and commercialization, protecting them from microbiological, chemical, physical and / or mechanical damage. Thus, the objective was to produce and characterize biopolymeric films based on sodium alginate and enriched with liquid from the cashew nut shell (CNSL) in different proportions, for later application in beef, in order to evaluate its effect on the preservation of this meat. product. For the characterization of the films, the design was completely randomized with four treatments (0%, 0.5%, 1% and 1.5% of inclusion of CNSL) and three repetitions, where uniform formation of the films was observed, in which the addition of LCC provided better thermal resistance, increased film thickness (p <0.05) compared to the treatment without inclusion, reduced luminosity (p <0.05) and increased (p <0.05) the color parameters red, yellow, saturation and the opacity index. The permeability increased as the level of CNSL increased (p <0.05), especially for concentrations 1% and 1.5% CNSL, where there was no significant difference between them (p> 0.05). Then, based on the best characterization results, two of these treatments (0 and 1% CNSL) were applied to beef from longissimus dorsi, together with control samples (without coating), where physicalchemical analysis, oxidation was performed lipid and microbiological analyzes related to the total mesophilic and psychrophilic counts, in an interval of 3 times (0, 3 and 6), observing that during the storage time, no statistical difference was obtained (p> 0.05) for the coordinates of L *, a * and b *. The pH of the control samples increased significantly (p <0.05), but the samples involved with an enriched CNSL coating maintained a stable pH. The CRA showed no significant difference (p> 0.05). PPC showed that the coating enriched with CNSL was able to improve the loss after cooking on the third day of storage. The HR decreased significantly (p <0.05), however the coating with inclusion of CNSL obtained the smallest reductions. In this treatment, there was also a decrease in lipid oxidation and less microbial growth of mesophiles. Therefore, it is recommended to use the film based on sodium alginate and with inclusion of CNSL at the level of 1%, in view of the efficiency of the results related to the characterization and subsequent application, believing that this product presents promising characteristics for preservation and consequent improvement of the quality of perishable foods.