In this study, olive leaf extract, grapefruit essential oil, orange peel essential oil, rosemary essential oil, and propolis were used alone and in different combinations against Escherichia coli O157: H7, Salmonella Enteritidis, E. coli Biotype 1, Listeria monocytogenes, and Staphylococcus aureus. The antibacterial activities of these materials were investigated using the disk diffusion method. Grapefruit essential oil created the highest zone of inhibition against pathogens. The two-in-one combinations of plant materials had the highest antibacterial effect against S. Enteritidis while the triple combinations had the highest antibacterial effect against E. coli O157:H7 among the Gram-negative bacteria. It was observed that the combinations of different numbers of materials that did not have antibacterial activity alone created a synergistic effect, but this effect was reduced through the suppression of the activity of certain materials in some combinations. As a result of the analysis of total phenolic content, the highest total phenolic content was observed in grapefruit essential oil. The antibacterial activity results of the plant materials used in the study and the results concerning the total phenolic amounts were consistent. Five plant materials and two of the three combinations of materials selected for the study were added to the patties for a sensory analysis. As a result of the panelists' evaluations of the color, appearance, odor, taste, texture, and overall acceptability criteria, it was determined that the meatball samples containing olive leaf extract had the closest results with reference to the control patties, and the triple combinations received the lowest appreciation scores.