Use of Essential Oils as Natural Food Preservatives: Effect on the Growth of Salmonella Enteritidis in Liquid Whole Eggs Stored Under Abuse Refrigerated Conditions

Abstract

<p>The steam distillation-extracted essential oils (EOs) of three aromatic plants from the Kabylie region of Algeria (<em>Eucalyptus globulus</em>, <em>Lavandula angustifolia</em>, and <em>Satureja hortensis</em>) were analyzed by gas chromatography coupled with mass spectrometry (GC/MS). The primary compounds from these EOs were 1,8-cineole (81.70%) for <em>Eucalyptus globulus</em>, 1,8-cineole (37.80%) and Beta-caryophyllene (20.90%) for <em>Lavandula angustifolia</em>, and carvacrol (46.10%), p-cymene (12.04%), and r-terpinene (11.43%) for <em>Satureja hortensis</em>. To test the antibacterial properties of the EOs, agar diffusion and microdilution methods were used for <em>Salmonella enterica</em> serovar Enteritidis CECT 4300. The results revealed that all of the EOs possessed a significant anti-Salmonella activity. The inhibition diameters for <em>Lavandula angustifolia</em> and Eucalyptus globulus were 41.30 and 35.26 mm, respectively, whereas the essential oil (EO) of <em>Satureja hortensis</em> showed a stronger anti-Salmonella activity (51.15 mm) when compared to the two other EOs. The minimum inhibitory concentration values ranged from 1 to 8 uL/mL, and the MIC value of the <em>Lavandula angustifolia</em> EO was the lowest (1 uL/mL). Moreover, the anti-Salmonella activity of the EOs added at various concentrations to liquid whole eggs was investigated, and the results showed that the antibacterial effect is proportional to the quantity of EO added to the product. Based on the observed anti-Salmonella activity, the EOs tested are promising natural alternatives for the preservation of liquid whole eggs stored at 7 ± 1ºC to simulate Algerian refrigeration conditions.</p>