LWT, cilt.64, sa.2, ss.540-546, 2015 (SCI-Expanded)
Linear low-density polyethylene (LLDPE) based novel active clay nanocomposite packaging films were prepared by twin-screw extrusion followed by blow molding. Layered structure of montmorillonite (MMT) and tubular structure of halloysite (HT) nanoclays loaded with thymol (thy), eugenol (eug) and carvacrol (crv) were used for polymer nanocomposite reinforcement. A novel liquid phase essential oil delivery method into the MMT surfaces/interfaces and HT surfaces/nano-channels was achieved using food grade surfactant Tween 80 for the first time in the literature. Effectiveness of active packaging films for controlling discoloration and Escherichia coli O157:H7 growth on fresh beef and native microflora (total mesophilic aerobic counts, lactic acid bacteria, yeasts-molds) and TBA value in Turkish type fermented sausage (sucuk) was investigated. Fresh beef color was maintained up to 4 days by active nanocomposite films and the thymol grafted films (thy-MMT and thy-HT) had bacteriostatic/bactericidal effect on E. coli O157:H7 during the beef storage. Native microflora of the sucuk was suppressed by vacuum packaging with active nanocomposite films. TBA formation was controlled by crv-MMT, thy- MMT and thy-HT up to 20 days. In conclusion, it might be suggested that active clay nanocomposite packaging films could be used to extend shelf life of the fresh and/or processed meats.