Quality Evaluation and Functional Properties of Industrial Cheese Supplemented with Clove Essential Oil

Cheese, as a fermented product based on milk, is alterable. Its alterability increases especially when it has high water content and it is high in fat, the case of the fresh double cream cheese. Faced with this situation, we have chosen, in the present study, to apply clove essential oil (CEO) in fresh double cream cheese in order to lengthen its conservation and to improve its antioxidant potential. In this work, CEO was extracted by hydro distillation, and then analyzed by GC-MS; 24 components of clove essential oil were identified. Eugenol was the major component (57.66%). Its anti- microbial properties against E. coli, Salmonella enteritidis and Staphylococcus aureus, were evaluated by disc diffusion method and minimal inhibitory concentration (MIC). As for, the antioxidant activity of CEO, it was evaluated by DPPH assay method. An optimum content of CEO (0.37%) was calculated by a mixing plan using Expert design software and was then added to the studied cheese. The responses, fixed from the beginning, for this mixing plan were: minimum inhibitory concentration (MIC), antioxidant activity (IC50), taste and odor intensity and global appreciation. The antioxidant activity (IC50 = 0.146) of cheese supplemented with the optimal content of CEO was found to be relatively important when compared to conventional cheese (IC50 = 0.477). In fact, incorporating CEO into cheese may significantly improve its oxidative stability. The antioxidant activity of cheese was unaffected by the 13-day storage period. Due to the antimicrobial properties provided by CEO, the fresh double cream cheese could be stored at refrigerated temperature with good taste and odour for a period of 13 days, implying that its shelf life could be extended.