The transfer rate of Salmonella Typhimurium from contaminated parsley to other consecutively chopped batches via cutting boards under different food handling scenarios. (November 2016)

• Record Type: Journal Article
• Authors: Faour-Klingbeil, Dima; Kuri, Victor; Todd, Ewen
• Is Part Of: Food research international. Volume 89(2016) Part 1
• Page Start: 495
• Page End: 503
• Publication Date: 2016-11
• Subjects: S. Typhimurium -- Parsley -- Transfer rate -- Cross-contamination -- Cutting surfaces; Food -- Analysis -- Periodicals; Food industry and trade -- Periodicals; Food industry and trade -- Canada -- Periodicals; Food Technology -- Periodicals; Food -- Periodicals; Food-Processing Industry -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Industrie et commerce -- Canada -- Périodiques; Aliments -- Recherche -- Périodiques; Food industry and trade; Canada; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.foodres.2016.09.001
• Languages: English
• ISSNs: 0963-9969

Abstract

Abstract: In many Mediterranean and Middle Eastern countries, leafy green parsley is typically eaten raw and prepared by fine chopping several batches. This study aimed to quantify the transfer rate of S . Typhimurium (Tr) across all chopped batches in scenarios that resemble normally occurring operations in restaurants and home kitchens. Fresh parsley leaves were inoculated at concentrations of 6 and 3 log CFU/g and chopped on a polyethylene cutting board (CB). Uninoculated parsleys were sequentially chopped in individual batches on the same cutting surface, 1) instantly (CB Instant), 2) after washing in water and holding at 30 °C 24 h (CBWW), 3) after washing in soapy water, sponge scrubbing and holding at 30 °C 24 h (CB SW). Using the high inoculum levels, the mean Tr was 0.012 ± 0.04, 0.014 ± 0.02 and 0.010 ± 0.008, via CB Instant, WW and SW, respectively. Comparatively, the Tr mean values were significantly higher with the low inoculum levels, 0.60 ± 0.65 and 0.64 ± 0.46, via CB Instant and CB WW respectively, and transmissions of S . Typhimurium significantly decreased across consecutively chopped batches on both washed CBs ( P < 0.05). These results demonstrated continuous transfer of Salmonella cells, from contaminated parsley to cutting boards and subsequently re-contaminating up to 6 batches of parsley chopped consecutively on the same surface. A greater cross-contamination rate was recorded during the initial phases of chopping and remained at 24 h at 30 °C. Vigilant cleaning and sanitation procedures on cutting surfaces should be a fundamental requirement after use with fresh produce, particularly if there is a likelihood of insufficient food safety measures at harvest and post-harvest stages. Graphical abstract: The population size of S . Typhimurium on successively chopped batches of parsley after initial chopping of artificially contaminated samples. A decreasing trend in the recovery of S . Typhimurium, particularly with high inoculum levels on source, along the three successive batches of un-inoculated parsley chopped subsequent to initially chopped 100 g parsley inoculated, a) instantly on same cutting board (CB Instant), b) after water wash of same cutting board and holding for 24 h at 30 °C (CB WW), c) after soap and water wash combined with soft sponge rubbing and holding for 24 h at 30 °C (CB SW). The latter scenario was not tested with low inoculum levels. *Initially chopped inoculated parsley (log CFU/g). L = low inoculum; H = High inoculum. Highlights: Transfer rate was strongly and negatively correlated with contamination levels. Transfer rate persisted in a diminishing trend across consecutively chopped parsley. Transmission of bacterial cells was reduced via washed cutting boards. Cross-contamination risk was recorded via cutting board held for 24 h at 30 °C.