Evaluation of whey protein concentrate coatings enriched with rosemary essential oil for enhancing the quality parameters and shelf life of white soft cheese

White soft cheese (WSC), a popular fresh dairy product in the Middle East, has a desirable texture and flavor but is highly perishable due to its high moisture and low acidity, which favor microbial growth. This study evaluated the antimicrobial efficacy of rosemary essential oil (REO) and its incorporation into whey protein concentrate (WPC) coatings for WSC preservation. Bacterial contaminants isolated from local WSC samples included Listeria monocytogenes, Salmonella spp. , Streptococcus pyogenes, Escherichia coli, Staphylococcus aureus, Aspergillus fumigatus, and Lactobacillus plantarum , confirming significant microbial contamination. REO exhibited broad-spectrum, dose-dependent antimicrobial activity against both Gram-positive and Gram-negative bacteria, with L. monocytogenes showing the highest sensitivity. Incorporating REO (0.6–1%) into WPC coatings improved their mechanical strength, moisture barrier properties, and antimicrobial performance without affecting solubility. During 28 days of refrigerated (4 °C) storage, uncoated cheeses showed rapid increases in bacterial, coliform, and fungal counts, whereas WPC–REO coatings, particularly at 1%, maintained microbial loads below detectable or acceptable limits. Coated samples retained higher moisture content, lower acidity, and more stable pH values than uncoated controls, indicating effective inhibition of post-acidification and spoilage. Sensory evaluation confirmed that REO-enriched coatings delayed deterioration in quality and preserved desirable flavor, aroma, texture, and overall acceptability throughout storage. Overall, REO-enriched WPC coatings function as biodegradable and multifunctional coatings that enhance microbial safety, physicochemical stability, and sensory quality of soft cheeses, offering a natural alternative to synthetic preservatives for extending shelf life and ensuring WSC safety.