Chitosan-starch film containing pomegranate peel extract and Thymus kotschyanus essential oil can prolong the shelf life of beef

Abstract The aim of the current study was to investigate the effects of pomegranate peel extract (PPE) and chitosan-starch (CH-S) composite film incorporated with Thymus kotschyanus essential oil (TEO) on the shelf-life of beef during storage period of 21 days at 4 °C. The physico-mechanical parameters, the color and Fourier Transform Infrared spectra values of the films were determined. Changes in odor, color, pH, thiobarbituric value for lipid oxidation levels and Pseudomonas spp. total viable counts, lactic acid and Listeria monocytogenes were determined during the storage time. All treated films showed lower elongation, strength and transparency values compared with chitosan - starch (CH-S) group. Results showed that CH-S-PPE 1%-TEO 2% treatment had the highest inhibition effect against L. monocytogenes. The bacterial counts and lipid oxidation were successfully inhibited using PPE and TEO. CH-S-PPE 1% group containing up to 2% TEO had the best acceptable sensory characteristic. Beef samples wrapped with CH-S film containing PPE and TEO also had longer shelf life.