Iron nanoparticles film on Aspergillus flavus inhibition

Abstract

Several treatments are applied to reduce or remove oxygen from packages and In contact with foods, aiming shelf-life extending. Metallic iron has been used as oxygen absorber agent in foods systems. This study aimed evaluates the action of iron nano-particles cellulosic matrix films on in vitro inhibition of Aspergillusjlavus. Iron nano-particles show larger contact surface which improve its oxygen absorber action. Plates containing A. JJavus spores at center were packed inside the following systems: PE/ Nylon package without addition of film (Cl), PE/Nylon package with addition of pure cellulosic matrix film (C2), PE/Nylon package with addition of iron nanoparticles film (T). The films were put inside the packages. It was measured the diameter variation of the colonies during 13 days. The oxygen concentration reduction inside the packages promoted by iron nanoparticles films showed significant effect (p<0.05) on inhibition of colonies growing. To the end of this period, the oxygen concentration inside all the packages reached values under 1% to all treatments, due the consumption by the fungus and the low permeability of the PE/Nylon package used. However, the oxygen level inside the packages submitted to T treatment was reduced more quickly, showed by inhibition on fungus growing. The mean of the colonies diameter values of A. Jlavus was significantly different (p<0.05), where C1 and C2 treatments did not differed each other (p>0.05), showing the higher values. The diameter means to the end of 13 days were 30, 28, 21 mm to Cl, C2 and T, respectively. Use of iron nanoparticles films inside PE/Nylon packages was effective on growth inhibition of A. Jlavus also avoiding the spore formation. This treatment can be used on growth inhibition of A. flavus on food packaged and contribute to the food safety.