Effect of Chitosan and Alginate-Based Edible Membranes with Oregano Essential Oil and Olive Oil in the Microbiological, Physicochemical and Organoleptic Characteristics of Mutton.

Edible chitosan or alginate coatings and their combinations with oregano essential oil or olive oil, have been examined for their effect on the microbiological, physicochemical and organoleptic characteristics of mutton. The results indicated that these edible coatings can contribute to maintaining good quality characteristics and extending mutton shelf-life. The total mesophilic counts in mutton ranged from 3.48 to 8.00 log 10 CFU/g, the total psychrophilic counts from 4.00 to 9.50 log 10 CFU/g, the B. thermosphacta counts from 2.30 to 7.77 log 10 CFU/g and the lactic acid bacteria counts from 2.00 to 5.85 log 10 CFU/g. Chitosan coatings significantly ( p < 0.05) reduced the total mesophilic, the total psychrophilic (1-2 log 10 cfu/g), the B. thermosphacta and the lactic acid bacteria counts in mutton. Alginate exhibited a lower L* value and a higher a* value and chroma compared with the control and chitosan lots. No significant differences were observed in the chemical composition of meat pieces among the experimental groups. Oregano oil positively affected the sensory attributes of meat. The most favourable combination, based on the microbiological counts, the organoleptic characteristics and the shelf-life extension of mutton, was that of chitosan with oregano essential oil.