Escherichia coli O157 and Staphylococcus aureus are significant foodborne pathogens that present challenges for effective removal from surfaces in food processing and healthcare environments. This study aimed to investigate the bactericidal effects of combined treatments using sodium dodecyl sulfate (SDS) with lactic acid and citric acid, alongside factors such as temperature and exposure time, to reduce E. coli O157:H7

and S. aureus on various surfaces. Bacterial strains were treated with varying concentrations of SDS, lactic acid, and citric acid at different temperatures over a range of exposure times. The bactericidal effectiveness of the combinations was first assessed in suspension, and the most effective combinations were selected for testing on ceramic, stainless steel, and plastic surfaces. Additionally, the impact of NaCl on SDS efficacy was evaluated. The results demonstrated that bacterial sensitivity varied between pathogens and surface types. E. coli O157:H7 and S. aureus showed enhanced sensitivity to SDS combined with lactic acid at higher temperatures, with the optimal combination of SDS 1% + 0.05% lactic acid at 45°C providing significant log reductions on surfaces. The optimized SDS–lactic acid combinations achieved up to a 6.24 log reduction in E. coli O157:H7 and a 4.5 log reduction in S. aureus, with complete inactivation observed on stainless steel and ceramic surfaces. The addition of NaCl notably reduced the bactericidal activity of SDS. Among surface types, stainless steel required the least contact time for bacterial removal, followed by ceramic and plastic, which necessitated longer exposure. In conclusion, combined solutions of SDS and an organic acid, particularly at elevated temperatures, are effective in reducing pathogenic bacteria on various surfaces. The SDS and lactic acid combination at 45°C is recommended as a potential disinfection method for E. coli and S. aureus on food and healthcare surfaces.