Cinnamon, Clove and Lavender Essential Oils As Effective Antibacterial Agents in Dairy Industry
Antibacterial essential oils gained increased interest as they are considered as safe and eco-friendly alternative to control food-borne pathogens. Thereby, it is important to study their combined effects in order to increase their efficiencies. This study was carried out using Syzygium aromaticum, Cinnamomum zeylanicum and Lavandula stoechas essential oils, either individually or in combinations, to enhance their anti-Staphylococcus aureus effects in contaminated milk. Initially, the chemical analysis of EOs was assessed by GS-MS. Then, their antioxidant potencies were evaluated through in vitro methods. Next, a specific matrix was established to determine the effect of each EO as well as their binary and tertiary combinations on S. aureus survivability in contaminated milk. Main results pointed out compositional differences between the studied samples. Indeed, the major compounds were camphor (35%), cinnamaldehyde (89%) and eugenol (75%) for lavender, cinnamon, and clove EOs, respectively. The same variability was also noticed considering their antioxidant activities. In addition, the anti-S. aureus activity data resorted that cinnamon EO was the most efficient sample capable to reduce this bacteria survivability to 37 106 UFC.ml-1. This efficiency was markedly ameliorated when adding clove and lavender EOs to reach 15 and 1.5 106 UFC.ml-1, respectively. The combination of the three sample limited S. aureus growth to 1.5 106 UFC.ml-1. As a result, cinnamon EO in addition to clove and lavender ones could be an interesting choice for food safety against S. aureus contamination, particularly in milk and dairy industries.
Key words - Essential oil, Combination, Milk, Staphylococcus aureus.