Antimicrobial and antioxidant coating based on basil seed gum incorporated with Shirazi thyme and summer savory essential oils emulsions for shelf-life extension of refrigerated chicken fillets

摘要

The present study was conducted to evaluate the effects of antimicrobial and antioxidant coatings based on basil-seed gum (BSG) on the refrigerated shelf-life of chicken fillets. Antimicrobial and antioxidant properties were developed by incorporating summer savory essential oil (SEO) and Shirazi thyme essential oil (TEO) emulsions, individually or in combination with each other, into BSG coating. Microbiological evaluations including total viable count (TVC), psychrotrophic (PBC) and lactic acid bacteria counts (LAB), as well as chemical charachteristics namely peroxide value (PV), thiobarbituric acid (TBA), total volatile basic nitrogen (TVB-N) and pH were performed on coated and control samples. Moreover, sensory evaluations were performed for odor, color, texture and overall acceptability. Results showed that incorporating SEO and TEO into BSG coatings could significanty 0.5) increase the quality of chicken fillets. Antimicrobial and antioxidant coatings significantly 0.05) reduced pH, TVB-N, PV and TBA values compared to uncoated control samples, specially for BSG/TEO coated samples, which resulted the best treatment. pH, TVB-N, PV and TBA in BSG/TEO coated samples were 5.96, 16.84, 3.33 and 2.44, respectively, lower than those of uncoated control samples on day 12 of storage. A similar reduction trend was observed for microbial population. TVC, PBC and LAB were 3.69, 4.73, and 3.87 log CFU/g on day 12 of storage in BSG/TEO coated samples lower than those of uncoated samples. Therefore, the natural active components of EOs showed positive effects on extending the shelf-life of coated chicken fillets. Besides, sensory properties of coated samples were significantly (p 0.05) better than those of control samples. Generally, TEO was more effective than SEO and no synergistic effect was observed between TEO and SEO.