بررسي ويژگي هاي نفوذپذيري فيلم هاي نانويي براي بسته بندي مواد غذايي

Investigation of Permeability Properties of food packaging Nanofilms

In recent years, extensive research in the production of impermeable packaging materials has been conducted with the aim of overcoming the limitation in the use of PVC and EVOV. One of the suitable candidates for this purpose is the use of nano particles in packaging films. These materials besides producing suitable relative impermeability, improve processibility and other properties while increasing the durability of food products. In this research, the effect of seven types of nanofilms containing silver and clay structures on permeability to water vapor and oxygen in comparison with control film (no nano particles) was investigated and the data were statistically analyzed. Results showed that the use of silver and clay nano particles reduces water vapor and oxygen permeability of films. In silver nanofilms, most reduction of permeability was obtained with the 2 percent silver nanofilm (S2) while in composite films, the 3 percent clay nanofilm (SC3) gave the best results, water vapor permeability showed a 3.1 to 4.9 times reduction compared to the control. The effect of film type on water vapor permeability was significant at the 0.05 level. Oxygen permeability was reduced by indirect method 1.7 to 4.9 times which is a considerable improvement over the regular film and is promising for the packaging industry. The effect of film type on oxygen permeability (indirect method) was significant at the 0.001 level. Oxygen permeability in the direct method showed a 1.75 to 3.8 reduction compared to the control (regular film) which was significant at the 0.01 level. In conclusion, nanofilm with 2 percent silver content (S2) exhibiting least amount of water vapor and oxygen permeability is the best film for packaging