Abstract

The purpose of this study was to compare chlorinated and ozonated water in reducing Salmonella typhimurium inoculated onto fresh ripe tomatoes. Surface-inoculated tomatoes were immersed/sprayed with chlorinated (200 mg l⁻¹) and ozonated water (1 and 2 mg l⁻¹) under 2 and 100 nefelometric turbidity units (NTU). Contact times were 120 and 30 s for immersing and spraying applications, respectively. Immersing in chlorinated water and low turbidity resulted in the most effective application with 3.61 log₁₀ bacterial reduction, while 1 and 2 mg l⁻¹ of ozone reduced 2.32 and 2.53 log₁₀, respectively. High turbidity and chlorine reduced the bacterial counts by 3.39 log₁₀, while 1 and 2 mg l⁻¹ of ozonated water and low turbidity reduced the bacteria by 1.48 and 1.92 log₁₀, respectively. Spraying chlorinated water reduced bacteria by 3 log₁₀, and ozonated water at 1 and 2 mg l⁻¹ reduced counts by 1.84 and 2.40 log₁₀, respectively. No statistical differences were found between chlorine and ozone (2 mg l⁻¹) during spraying applications (p < 0.05). The use of ozonated water both in immersing and spraying applications is suggested when water turbidity remains low.