标题：Thymus vulgaris (red thyme) and Caryophyllus aromaticus (clove) essential oils for controlling spoilage microorganisms in pork under modified atmosphere
摘要：In recent years, it has been confirmed that essential oils (EOs) exert antimicrobial activity, as they are able to inhibit cell growth and even inactivate microbial cells. The application of biopreservation strategies by means of EOs opens up interesting perspectives in the food industry, including meat production. The paper aims to evaluate the effects of dipping with Thymus vulgaris (red thyme) and Caryophyllus aromaticus (cloves) EOs on the development of the spoilage population of fresh pork packaged under modified atmosphere (MAP). In particular, the research was focused on Brochothrix thermosphacta , a specific spoilage microorganism of fresh meat packed in anaerobic conditions or under MAP. Among seven EOs, those that showed the highest antimicrobial activity on 5 B. thermosphacta strains in vitro were: cloves [minimum inhibitory concentration (MIC) 0.6-2.5 mg/mL], savory (MIC 2.5-5.0 mg/mL) and red thyme (MIC 2.5 to 20 mg/mL). Red thyme and cloves EOs were selected for the meat treatment, by increasing the dose at 20 and 40 mg/mL to take into account the matrix effect that can reduce EO availability. In spite of the minor efficacy observed in vitro, 40 mg/mL red thyme EO strongly contained the growth of B. thermosphacta in pork samples up to Day 6 of storage (below 3.0 Log CFU/g, starting from 2.0 Log CFU/g at time 0), and exterted antimicrobial effect also on the aerobic mesophilic count. Good results were obtained also with 20 mg/mL red thyme EO. The containment of B. thermosphacta growth through EOs encourages research on alternative methods for extending the shelf-life of fresh meat under MAP.
