Population Dynamics of Enteropathogenic Bacteria in Pulp of Salad Vegetables

Abstract

In this study, we optimized microbial killing methods specific to tomato, carrot and cucumber pulp were optimized by applying different treatments, moist heat, dry heat and UV-C irradiation. The ability of Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella flexneri, Aeromonas hydrophila, Staphylococcus aureus and Salmonella enterica to grow on tomato, carrot, cucumber and onion pulp was investigated. Population of A. hydrophila and S. enterica were high in tomato, carrot and cucumber. The population of A. hydrophila was maximum at 36 h in tomato and carrot while it was high in cucumber at initial 24 h. The population of S. enterica was maximum at 24 h in tomato, 36 and 48 h in carrot and 48 h in cucumber. Onion pulp supported less growth of bacteria. The observed difference in the ability of different bacteria to grow in different vegetable pulp warrants development of vegetable specific sanitizing methods to avoid salad-borne enteropathogenic infection.