Comparative Efficacy of Various Vinegars in Reducing Bacterial Load and Inhibiting Foodborne Pathogens

Abstract

Background: Although leafy vegetables are utilized extensively in Iraqi cuisine, yet it loads various microbial contaminants that may lead to foodborne diseases, food poisoning, and food spoilage.

Objectives: The purpose of the present study was to evaluate the use of natural products (4 vinegar types) in sterilization and disinfection of leafy vegetables.

Methodology: This laboratory-based experimental study was conducted in the Department of Biology, College of Science, University of Baghdad, Baghdad, Iraq. This study was carried out from November 2024 to January 2025. The isolation of pathogenic bacteria from leafy vegetables collected from the Baghdad city market. Using well diffusion techniques, the presented work sought to assess the antibacterial properties of four vinegar types-grape, date, white vinegar, and apple cider and the impact of vinegar concentration, type, and exposure duration on the bacterial load in leafy vegetables by Pour plating on PCA (Plate Count Agar).

Results: (6) Salmonella typhi, (10) Pseudomonas aeruginosa, and (6) Shigella species were isolated from 25 distinct leafy vegetables basal, celery, parsley, watercress, leek, spinach, and mint. Salmonella Typhi showed sensitivity to vinegar through inhibitory diameters ranging between 25, 28, 35, and 35 mm, and Shigella (15, 20, 28, 28 mm) for date, grape, apple, and white vinegar, respectively. Pseudomonas aeruginosa was resistant to all vinegar types The microbial load regarding food has been examined using six vinegar concentrations, such as 1.0%, 2.0%, 3.0%, 4.0%, 5.0%, and 6.0%, as well as exposure times like 10, 20, and 30 minutes for each one of the four types of vinegars such as grape, date, apple, and white. With regard to each one of the vinegar samples, aerobic colony counting has been carried out through pour plating on PCA (Plate Count Agar). On the bacterial load, white vinegar has the strongest effect, followed by apple, grape, and date. A significant factor in reducing the bacterial load is extending the treatment period and raising the vinegar content.

Conclusion: Pseudomonas aeruginosa is resistant to all types of vinegar; however, vinegar samples from dates, grapes, cider apples, and white vinegar have antibacterial activity against the two studied bacteria, Salmonella Typhi and Shigella species. Date vinegar was the least effective at lowering the number of bacteria, whereas white vinegar was the most successful. Vegetables and fruits could be safely disinfected with vinegar, although the type of vinegar, concentration, and exposure duration all affect antibacterial activity.

Bangladesh Journal of Infectious Diseases, June 2026;13(1):96-103