Effect of edible chitosan-rosemary coating on quality and shelf life of refrigerated chicken fillets

Chicken breast meat (fillet) is favored by consumers worldwide but it is prone to rapid spoilage, therefore, food industries are nowadays seeking technologies to increase its shelf-life. Spoilage of fresh poultry products is an economic burden to the producer. Furthermore, as consumer's demand for more “healthier” meals (free of conventional chemical preservatives) has increased in the last decade. Chitosan, a deacetylated form of chitin, is a polysaccharide found in the shells of crab and shrimps and the cell walls of fungi. Chitosan has been proved to be non-toxic, biodegradable and biocompatible. Essential oils derived from plants have been recognized for decades to exhibit biological activities, including antioxidant, anticancer and antimicrobial attributes. The present study was conducted to evaluate the effect of chitosan edible coating (2%) containing rosemary essential oil (1%) on the shelf life and keeping quality of chicken breast meat at refrigerated storage temperature. Samples were separated into three groups; uncoated (control), treated with acetic acid 1% and coated with chitosan containing rosemary essential oil. Samples were stored at 4±1°C up to 15 days and evaluated periodically (on days 0, 3, 6, 9, 12 and 15) for microbiological (mesophilic and psychrotrophic bacterial counts), chemical (pH, TBA, TVN) and sensory (external aspect, muscular elasticity, odor and color) characteristics. Microbial analysis indicated that coating had significant effects (P