Production of edible nano chitosan- Iranian tragacanth gum film enriched with Eryngium campestre essential oil and its effect on microbial spoilage of goat meat

Abstract

This study aimed to investigate the effectiveness of a composite film comprising nano chitosan and Iranian tragacanth gum (NC-G), supplemented with Eryngium campestre essential oil (EO), in preserving the microbial quality of refrigerated goat meat at 4°C. Five film treatments were prepared, including NC + NC-G, and NC-G combined with 0.5%, 1%, and 1.5% EO. The antimicrobial efficacy of these films was evaluated against four microorganisms. Subsequently, these film treatments, along with an untreated control, were monitored for microbial changes [total viable count (TVC), psychrotrophic count (PTC), lactic acid bacteria, and Enterobacteriaceae] over a 16-day storage period. Results demonstrated significant antimicrobial activity of the films against tested pathogens, with effectiveness increasing with higher EO concentrations (p< 0.05). Staphylococcus aureus showed the highest susceptibility among the bacteria, while Pseudomonas aeruginosa exhibited the greatest resistance. Application of the nanocomposite film with EO effectively delayed microbial spoilage of goat meat, with TVC and PTC counts in treatments containing 1% and 1.5% EO remaining below the spoilage threshold (7 Log CFU/g) by the end of storage. Overall, findings suggest that incorporating EO into the nanocomposite film inhibits factors contributing to microbial spoilage in goat meat. Given similar inhibitory effects observed at 1% and 1.5% EO concentrations and considering economic factors, a concentration of 1% EO can be regarded as optimal.

Keywords

• plant essential oil
• biodegradable film
• meat
• antimicrobial activity
• pathogenic bacteria