Evaluation of Household Sanitizers for Reducing Levels of Salmonella typhimurium on Iceberg Lettuce and Rocket Leaves

The effect of various household sanitizers including water, water acidified with white vinegar (1.5%), vinegar and lemon juice were evaluated for their effectiveness in reducing counts of Salmonella typhimurium on rocket and lettuce leaves. Treating rocket and lettuce samples with water containing 1.5% vinegar for 30 min or washing with water (at 28C) for 5 min showed negligible reduction in pathogen counts. Sanitizing rocket leaves with vinegar or lemon juice alone caused significant reductions in pathogen count of 2.3 and 2.5 log10 CFU/g respectively. A maximum reduction ranged from 3.1 log10 CFU/g to an undetectable level was recorded after dipping rocket leaves with high (5.8 log10 CFU/g) and low (4.0 log10 CFU/g) inoculums in a mixture of lemon juice and vinegar for 30 min exposure time respectively. A reduction of 2.4 was obtained when lettuce leaves with high load (5.1 log10 CFU/g) were dipped in vinegar-lemon mixture for 30 min. However all treatments; vinegar, lemon and their mixture significantly reduced the bacterium load on lettuce with low inoculum (4.0 log10 CFU/gm) to an undetectable level. Rocket and lettuce samples treated with vinegar, lemon or their mixture were analyzed for consumer acceptability by sensory evaluation using a 9-point hedonic scale. The results suggested that the use of these disinfecting treatments reduced pathogen loads on rocket and lettuce more effectively and did not negatively affect the important sensory characteristics of the plants. 1 Faozia A. Ibrahim, 2 Radya A. Mustafa, 1 Suleiman Abusalloum, 2 M.S. Eljadar 1 Depertment of Food Science and Technology, University of Omer El-Mukhtar. 2 Faculuty of veterinary, University of Omer