Avaliação da difusão de prata em salsichas recobertas com filmes comestíveis contendo nanopartículas antimicrobianas

Abstract

Lactic acid bacteria slime producing in sausages can have their growth inhibited by means of edible coatings that contain in their formulation antimicrobial compounds. Silver nanoparticles (AgNPs) are known antimicrobial agents that may be synthesized by green methods, allowing its application in foods. However, its use is only suitable in low concentrations due to possible cumulative effects on the human body. Thus the objective of this work was the green synthesis of silver nanoparticles and their application on edible starch film in sausages to control the growth of lactic acid bacteria. The sausages were evaluated during time intervals of 0, 15 and 30 days regarding on concentration of AgNPs by Mass Spectroscopy Inductively Coupled Plasma (ICP-MS) and to its texture by the “texture profile analysis” (TPA). The sausages were initially subjected to washing, cooking and finally crushed. Samples were taken at every step of preparation for ICP-MS evaluation. Samples removed from cooking water indicated that the highest concentration of AgNPs remains at this stage. The concentration of AgNPs at the crushed sausages remained at 0.5 µg / L for 15 and 30 days storage. Analysis of sausages texture profile showed that after thirty days of storage there was significant difference between the adhesion parameters, hardness and gumminess for both treatments, control and covered by AgNPs. These differences were related to the growth of lactic acid bacteria at control sausages drove to protein oxidation and consequent in lipid oxidation. On the other hand the sausage covered with AgNPs controlled bacterial growth and did not presented texture variation.