The antimicrobial effect of basil seed mucilage-ZnO nanocomposite coating on the quality of cheddar cheese during ripening

Cheddar cheese is a hard type of cheese. It is coated traditionally by a special wax. Commercial coating materials which are used for coating are non-edible as a result they are undesirable due to environmental pollution and allergies caused in some consumers. Today, biodegradable films are receiving more attention. In this study, the effect of edible coating of basil seed mucilage containing zinc oxide nanoparticles (ZnO-NP) in three levels of zero, 0.25 and 0.5% on the quality properties of cheddar cheese was investigated during ripening for 90 days. The results of experiments showed that at the end of ripening, the highest amount of salt and fat and the lowest amount of moisture were related to the sample with mucilage coating containing 0.5% of ZnO-NP. Also, during ripening, in all samples the number of non-starter lactic acid bacteria increased, but the number of starter bacteria increased first and then decreased (p < 0.01). Also, in all treatments, the total number of mesophilic aerobic bacteria, Pseudomonas, mold and yeast increased significantly during storage, which was the lowest in samples with coating containing ZnO-NP (p < 0.01). In addition, ZnO-NP coatings prevented mold growth on the surface of cheddar cheese samples. According to the results obtained of this study, basil seed mucilage containing 0.5% ZnO-NP can be used as a coating in cheddar cheese without any adverse effect on the flavor of cheese.