Increased shelf life of Oncorhynchus mykiss (Rainbow trout) through Cu-Clay nanocomposites

Microbial growth is widely responsible for shortened shelf life of cold water-living fish products. So, it seems that current chemical-based food packaging has no acceptable efficacy, and food industrialists tend to the usage of more novel approaches like active food packaging. Among them, there is a great research interest in nanotechnology-emerging approaches. This study aimed to investigate the anti-microbial efficacies of Polyethylene/CuNP/nanoclay nanocomposites to enhance the shelf life and physiochemical features of rainbow trout. Three main nanocomposites with various concentrations of Cu and clay nanoparticles were examined. SEM, XRD, and EDX (as physiochemical analysis), disk diffusion (as antimicrobial assays), total volatile nitrogen (TVB-N), and peroxide value (PV) (as biochemical parameters) were measured. Based on the results, nanocomposites could reduce the microorganism growth rate by reducing the number of colonies (33.3%), inhibitory activities against both gram-positive (8 mm) and gram-negative bacteria (10 mm), maintenance of TVB-N (42% reduction), and PV (44% reduction) below the standard range. To sum up, these new nanocomposites can be a good candidate to enhance the shelf life of Rainbow Trout.