Production of Functional Cooked Sausage by Mentha piperita Essential Oil as a Natural Antioxidant and Antimicrobial Material

Background: Natural antioxidants with plant origin are incorporated to foods in the forms of essential oils or extracts. They can retard lipid oxidation and control spoilage bacteria in foodstuffs (e.g. meat products). Objective: This work was aimed to evaluate the effect of nitrite partial replacement with Mentha piperita essential oil (MPEO) on oxidative, microbial and sensory properties of cooked sausage. Methods: GC/MS was used for the identification of essential oil components. Nitrite content (120 ppm) was reduced and replaced with 20, 40 and 60 ppm of MPEO. The effect of MPEO on product rancidity was assessed by peroxide and TBARS values in sausage samples. Antimicrobial properties of the essential oil were evaluated by MICs and MBCs determination against Escherichia coli and Clostridium perfringens by microdilution method. Also, the effect of this replacement on the product color stability was evaluated by determination of L*, a* and b* values, Hue angle, and E (2-30). Result: Results indicated that peroxide and TBARS values of sample with 20 ppm of MPEO were significantly lower than samples with 40 and 60 ppm of MPEO and control, at the end of storage period. With respect to color parameters, hue angle of the sample with 60 ppm of MPEO was significantly higher than samples with lower essential oil levels and control after 30 days of storage. Moreover, total color difference of sample with 60 ppm of MPEO was lower than other samples and control (p<0.05). Antimicrobial activity of MPEO against Escherichia coli determined as MICs and MBCs were 0.226 and 0.453 mg/ml, respectively. These values turned out as 0.453 and 0.906 mg/ml against Clostridium perfringens. Conclusion: all samples with different essential oil levels were acceptable after 30 days of storage according to PV and TBARS thresholds determined in literature. Replacement of 50 % of nitrite with MPEO is a reasonable approach in order to put down harmful effects of nitrite in sausage and to enhance functionality of the product.