Sustainable camel meat preservation using individual and synergistic essential oil bioactive compounds against Listeria monocytogenes

Camel meat is an emerging and sustainable meat with a favorable nutritional profile; however, it is highly susceptible to microbial contamination, particularly Listeria monocytogenes. This study assessed the antimicrobial efficacy of four essential oil (EO) bioactive compounds—linalool, eugenol, α-pinene, and α-terpinene—used individually and in binary combinations against L. monocytogenes in vitro and in minced camel meat stored at 4 °C for 12 days. Minimum inhibitory concentration (MIC) assays revealed that eugenol showed the strongest antibacterial activity (1.25 mg/mL), followed by linalool (5 mg/mL), while α-pinene and α-terpinene exhibited weak activity (40 mg/mL). Checkerboard analysis identified four synergistic combinations—linalool + α-pinene (LP), linalool + eugenol (LE), eugenol + α-pinene (EP), and eugenol + α-terpinene (ET)—with fractional inhibitory concentration index (FICI) values ≤ 0.5. Based on FICI findings, individual EO bioactive compounds (1% w/w) and their synergistic combinations (1% and 2% w/w) were incorporated into minced camel meat inoculated with L. monocytogenes. Eugenol achieved the highest individual reduction by day 12 (3.9 log CFU/g), followed by linalool (2.3 log CFU/g), while α-pinene and α-terpinene were ineffective. All 2% combinations completely inhibited L. monocytogenes from day 3 onward, and the LE1 treatment achieved complete inhibition by days 9 and 12. These findings highlight the strong potential of essential oil bioactive components, particularly their synergistic combinations, as promising natural interventions for enhancing the microbial safety of camel meat and warrant further exploration toward multiple strains, different pathogens and industrial application.