Uso de revestimento comestível com nanopartículas de quitosana e óleos essenciais no controle de Listeria monocytogenes e Leuconostoc mesenteroides em salsicha

Abstract

Meat products have intrinsic characteristics that favor the development of foodborne pathogens and spoilage microorganisms, which can compromise the safety and quality of the product. Among them, Listeria monocytogenes, a pathogen of great concern in the food industry, and Leuconostoc mesenteroides, a lactic acid bacterium associated with the spoilage of meat products. Controlling these microorganisms is of great importance in the food sector; therefore, preservatives that address consumer demand for healthier products are particularly important. The use of essential oils (EOs) as natural preservatives to control microbial contamination of food has been extensively studied and their incorporation into edible coatings appears as an alternative to increase their effectiveness and reduce their sensory interference. Thus, the objective of this study was to develop edible coatings with nanoparticles of chitosan extracted from squid pens and EOS to control L. monocytogenes and L. mesenteroides inoculated in sausage. For this purpose, the minimum bactericidal concentrations (MBC) of the oregano, clove, coriander and marjoram EOS were determined by the broth microdilution method. Based on the MBC values and using the Rotational Central Composite Design (RCCD), different combinations between the EOS were generated and evaluated in vitro on L. monocytogenes and L. mesenteroides. Subsequently, edible coatings with chitosan nanoparticles and different combinations of EOS were developed, characterized and applied to sausages that were packaged and stored at 7°C for 20 days. Three treatments were evaluated, namely T1 (chitosan nanoparticles coating), T2 (chitosan nanoparticles coating + 0.15575% oregano EO + 0.15575% clove EO + 0.53075% marjoram EO), T3 (chitosan nanoparticles coating + 0.21875% oregano EO + 0.21875% clove EO + 0.40625% coriander EO) and a control without coating. The EOS showed bactericidal activity when tested in vitro, alone or in combination. A lower count (CFU/g) of bacteria was observed in the treatments containing chitosan nanoparticles and EOS. The coatings reduced water activity, but did not significantly interfere with the pH, TBARS values, and color of the sausages. Thus, the use of edible coatings with chitosan nanoparticles and EOS may be an alternative for controlling pathogens and spoilage microorganisms in meat products.