Effect of storage temperature on thyme and bay laurel essential oil emulsions as preservatives against foodborne pathogens in cooked chicken

Abstract This study evaluated the impact of storage temperature on the antimicrobial activity of essential oil emulsions of Thymus vulgaris L. (TEOE) and Laurus nobilis (LEOE) at 0.6% against Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 14579), and Listeria innocua (ATCC 33090) inoculated onto cooked chicken breast to simulate post-cooking contamination. Samples stored under: T3 (regular storage at 3 ± 0.5 °C), T8 (inadequate storage 8 ± 1 °C), and T3A (refrigerated storage with simulated temperature abuse at 25 ± 1 °C). Microbial analysis and sensory evaluations were carried out at 0, 24, 36, 72, and 120 h of storage. The GC-MS analysis showed that carvacrol 31.97% and eucalyptol 41.16% were the main components in TEO and LEO, respectively. Storage temperature influenced the antibacterial effect of EOE. TEOE exhibited greater effectiveness at T8 compared to T3, reducing microbial counts to 1 log CFU g −1 . Conversely, LEOE demonstrated superior efficacy under T3 in most instances and received a higher acceptability score. Additionally, at T3A, both emulsions demonstrated comparable effectiveness against all bacterial strains, although a slight reduction in antimicrobial proprieties were noted after simulated temperature abuse at 24 h. Therefore, the optimal combination for preserving cooked chicken meat is TEOE under T8 or LEOE under T3; assuming post-cooking contamination.