The antibacterial effect of EOs against the growth of S. aureus, E. coli, and L. monocytogenes was established by the agar disc diffusion method, and the results are presented in Figure 8. On Mueller–Hinten (MH) agar plates, the inhibition zones of S. aureus are 64.7 ± 1.2 mm for thyme oil, 27.8 ± 3.4 mm for tea tree oil, 27.8 ± 4.0 mm for clove oil, and 12.8 ± 4.3 mm for rosemary oil. For E. coli, the inhibition zones are 35.5 ± 4.6 mm for thyme oil, 27.0 ± 3.4 mm for tea tree oil, 19.5 ± 0.5 mm for clove oil, and 15.1 ± 0.5 mm for rosemary oil. The diameters of the inhibition zones in the case of L. monocytogenes growth are of 69.5 ± 6.4 mm for thyme oil, 22.0 ± 2.8 mm for tea tree oil, and 28.5 ± 2.1 mm for clove oil. There is no inhibition zone for rosemary.