In recent years, the tendency to use antimicrobial edible film and coating has increased, which has increased the quality, safety and shelf life of food. Cheese is one of the most important dairy products that has a special nutritional value in human nutrition. UF-Feta cheese, which is a type of cheese, is contaminated by microorganisms such as coliforms, spore-forming bacteria and lactose-fermenting yeasts. The causative agent of listeriosis, Listeria monocytogenes, is transmitted through the

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... onsumption of cheese. In this study, the effect of composite edible coating based on chitosan and whey protein containing titanium dioxide (TiO2) nanoparticles and Zataria multiflora essential oil on shelf life, microbial, physicochemical and sensory properties of UF-Feta type cheese was investigated. Furthermore, the inhibitory effect of films from coating solutions on the growth of Listeria monocytogenes was also investigated. Materials and Methods: Chitosan, whey protein isolate (WPI) (higher than 91% protein), Zataria multiflora essential oil (ZEO), TiO2 nanoparticles, and glycerol were procured from Bio Basic (Canada), Hilmar Canada, Barij-Essence Co. (Iran), Acros Co. (USA), and Merck Co. (Darmstadt, Germany), respectively. In order to prepare the coatings, a solution of WPI and chitosan was prepared separately. Whey protein suspension (3%, w/v) was made by dispersing WPI in DDW subsequently heated at 90°C for 30 min at pH value of 8.0 and then cooled rapidly. Chitosan solution (10 g/L) was made by dispersing chitosan in 2% (v/v) acetic acid solution with constant mixing for 3 h at 60°C. Based on preliminary experiments, whey protein–chitosan suspension was made using blending two polymer suspensions at constant ratio of WPI/chitosan (70:30) and mixed magnetically for 15 min at 25ºC. In the next step, TiO2 NPs (1 and 2% w/w) were incorporated and after mixing for 15 min, glycerol (30% w/w) was incorporated to the composite suspension and again stirred for 30 min. Next, ZEO (0 and 1% v/v) was incorporat [...]