Inhibitory Effect of Three Plant Essential Oils against Dominant Spoilage Bacteria in Processed Beef Steak

The dominant spoilage organisms in processed beef steak were identified by the combined use of the traditional culture method and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The plant essential oil with the strongest antibacterial activity was selected from clove, cardamom, and black pepper essential oils based on inhibition zone diameter, minimum inhibitory concentrate (MIC), minimum bactericidal concentration (MBC) and bacterial growth curve. The results showed that the dominant spoilage bacteria in processed beef steak were Janthinobacterium lividum, Pseudomonas putida and Brochothrix thermosphacta; the inhibition zone diameter of clove essential oil against each of these bacteria was greater than 10 mm, and the growth and reproduction of the dominant spoilage bacteria were significantly inhibited by the addition of the essential oil at 2–4 μL/mL; the inhibitory effect of cardamom essential oil was slightly weaker; and the essential oil of black pepper did not have a significant inhibitory effect on any of the three dominant spoilage bacteria.