Production of Polyethylene Composite Containing Silver Nanoparticles to Increase the Shelf Life of Mushrooms in Refrigerator Temperature

In this study, active polyethylene films containing silver nanoparticles to increase the shelf life of mushroom were produced. For this purpose, silver nanoparticles with different levels (0, 0.5, 1, 2 and 3% based on polymer weight) were added and its effect on the characteristics of the mushroom, microbial characteristics and sensory properties was evaluated. Mushrooms were stored at 4 °C for 12 days and physicochemical characteristics were analyzed after 0, 4, 8 and 12 days of storage. Increasing the concentration of nanoparticles in the polymer structure leads to decreasing weight loss and total soluble solid changes in mushroom samples compared to the control sample. The increasing the concentration of silver nanoparticles significantly (p<0.05) reduced the loss of firmness in the samples. The L* value changes of the mushrooms coated with polymer-silver nanoparticles was lower than the control samples. A significant (p<0.05) decrease in L* value and a significant (p<0.05) increase in a and b values occurred in all mushrooms during the maintenance period. The use of polymer-silver nanoparticles coating led to significant (p<0.05) decrease in number of microorganisms of the mushrooms during all days of storage compared to the control sample. Incorporation of silver nanoparticles caused decrease in microbial count of the coated samples. In all treatments, increasing the silver nanoparticles level caused to improve the physicochemical, microbial and sensory properties of mushroom samples. Based on sensory evaluation was found that using the polyethylene film containing 3% the silver nanoparticles led to significantly increasing (p<0.05) of sensory parameter scores, so that the treatment wrapped with the polymer containing 3% the nanoparticles had the highest acceptability score (5 out of 5) compared to control and other treatments. Overall it can be concluded that utilization 3% silver nanoparticles in the polymer structure resulted in the desirable physicochemical and microbial quality and sensory properties in the mushroom samples.