EFFECT OF SANITIZER TREATMENTS ON SALMONELLA STANLEY ATTACHED TO THE SURFACE OF CANTALOUPE AND CELL TRANSFER TO FRESH-CUT TISSUES DURING CUTTINGPRACTICES

Authors: Ukuku, Dike; Sapers, Gerald

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/12/2001
Publication Date: 3/12/2001
Citation: N/A

Interpretive Summary: The ability of Salmonella stanley to attach and survive on cantaloupe surfaces, how the attached pathogen reacted to chlorine or hydrogen peroxide treatments, and its transfer to the interior tissue during cutting was investigated. Cantaloupes were immersed in an inoculum containing S. stanley (8 log CFU/ml) for 10 min and then stored at 4 C or 20 C for up to 5 days. Periodically, the inoculated melons were washed with chlorine (100 ppm) or hydrogen peroxide (5%) and fresh-cut tissues were prepared. A population of 3.8 log10 CFU/cm2 of S. stanley was recovered from the inoculated cantaloupe surfaces. Salmonella attached on cantaloupe surfaces stored at 4 C or 20 C survived for up to 5 days, and the population was not reduced after washing with water. S. stanley was recovered in fresh-cut pieces prepared from inoculated whole cantaloupes with no sanitizer treatment. Washing with chlorine or hydrogen peroxide solutions was most effective immediately after inoculation resulting in an approximate 3.0 log10 CFU/cm2 reduction and the level of recovered Salmonella population transferred to fresh-cut samples was reduced to below detection. The effectiveness of both treatments diminished when inoculated cantaloupes stored at 4 C or 20 C for more than 3 days were analyzed, and the fresh-cut pieces prepared from such melons were Salmonella positive. Salmonella outgrowth occurred on inoculated fresh-cut cubes stored above 4 C.

Technical Abstract: The ability of Salmonella stanley to attach and survive on cantaloupe surfaces, its in vivo response to chlorine or hydrogen peroxide treatments, and subsequent transfer to the interior tissue during cutting was investigated. Cantaloupes were immersed in an inoculum containing S. stanley (8 log 10 CFU/ml) for 10 min and then stored at 4 C or 20 C for up to 5 days. Periodically, the inoculated melons were washed with chlorine (1000 ppm) or hydrogen peroxide (5%) and fresh-cut tissues were prepared. The incidence of S. stanley transfer from the rinds to the fresh-cut tissues during cutting practices was determined. A population of 3.8 log10 CFU/cm2 of S. stanley was recovered from the inoculated rinds. No significant (p < 0.05) reduction of the attached Salmonella population was observed on cantaloupe surfaces stored at 4 C or 20 C for up to 5 days, and the population was not reduced after washing with water. S. stanley was recovered in fresh-cut pieces prepared from inoculated whole cantaloupes with no sanitizer treatment. Washing with chlorine or hydrogen peroxide solutions was most effective immediately after inoculation resulting in an approximate 3.0 log10 CFU/cm2 reduction and the level of recovered Salmonella population transferred to fresh-cut samples was reduced to below detection. The effectiveness of both treatments diminished when inoculated cantaloupes stored at 4 C or 20 C for more than 3 days were analyzed, and the fresh-cut pieces prepared from such melons were Salmonella positive. Salmonella outgrowth occurred on inoculated fresh-cut cubes stored above 4 C.