Effectiveness of Acidified Sodium Chlorite and Other Sanitizers to ControlEscherichia coliO157:H7 on Tomato Surfaces

Abstract

The use of a suitable sanitizer can reduce the risk of produce-related foodborne illnesses. We evaluated the effectiveness of several sanitizers to reduce inoculated Escherichia coli O157:H7 on the surface of cherry tomatoes (Solanum lycopersicum var. cerasiform). Depending on the method of inoculation (dipping/spotting), each of 80 g (eight tomatoes) of inoculated cherry tomatoes was washed in 400 mL of sanitizer solutions or 400 mL distilled water for 5 minutes. The effectiveness of sanitizers on spot-inoculated E. coli O157:H7 on tomato surfaces was found higher than on dip-inoculated tomatoes. Washing with water or chlorine water (0.1 g/L as free chlorine) could reduce 1.3 log CFU/g of E. coli O157:H7 in dip-inoculated (6.8 log CFU/g) tomatoes. Washing with lactic acid (LA) solution (1.0 g/L), phytic acid solution (1.0 g/L), calcinated seashells (oyster/sakhalin surf clam), and 1.0 g/L chitosan in 0.5 g/L LA (Chito) did not exhibit a significant higher effectiveness than that of water wash alone (1.0 log CFU/g). Acidified sodium chlorite (ASC) solution prepared from 0.5 g/L of sodium chlorite and 1.0 g/L LA or phytic acid reduced 3.5 log CFU/g of E. coli O157:H7 in dip-inoculated tomato surfaces. ASC (0.5 g/L of sodium chlorite and 1.0 g/L of LA) wash followed by a second wash with LA exhibited an additional sanitary effectiveness compared to a single wash with ASC. However, washing with ASC followed by a second wash with Chito exhibited an additional 1.0 log CFU/g reduction compared to a secondary wash with water. No significant difference of color, taste, and texture was observed among the washed cherry tomatoes.

Shelf life extension of fresh fruit and vegetables by chitosan treatment

“…Some studies have reported on the antibacterial activities of chitosan films against foodborne pathogens of fresh fruit and vegetables (Table 9). Inatsu et al (2010) evaluated different sanitizers to prevent growth of four strains of E.…”

Meta-analysis of the Effects of Sanitizing Treatments on Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes Inactivation in Fresh Produce

“…As a fourth criterion, an approved microbiological method for pathogen enumeration had to be employed. Considering all of those requirements, 40 primary studies were regarded as appropriate for inclusion in the present meta-analysis study (19)(20)(21)(22)(23)(24)(25)(26).…”

“…The phenomenon of cross-contamination during produce washing has been indicated as the potential cause of the spinach E. coli O157:H7 outbreak that resulted in 205 illnesses and three deaths in the fall of 2006 in the United States (17, 18). As disinfection of fresh produce constitutes a critical control point, several reports quantify the pathogens' concentrations in these foods before and after disinfection with different sanitizers (19)(20)(21)(22)(23)(24)(25)(26). However, because the log reductions of pathogens attained by the sanitizers are affected by the particular conditions or study characteristics (protocols for washing, type of fruit and vegetable, whole or cut fresh produce, type of sanitizer and concentration, washing time and temperature, pathogenic strains, microbiological essays, etc.)…”

Effectiveness of Stable Ozone Microbubble Water on Reducing Bacteria on the Surface of Selected Leafy Vegetables

“…Bactericidal effectiveness of ozone microbubble water on vegetable leaves The experimental methods were the same as previously described (Elano et al, 2010;Nei et al, 2009;Inatsu et al, 2010b) except for small modifications. OW was generated with a flow-type electric ozone generator (Do-30, Kobe Steel, Ltd., Kobe, Japan) and was used within 5 min.…”

“…Instead of the washing treatment, exposing the vegetables to 100 mg/L of GO in plastic bags was also performed. A standard agar plate and desoxycholate agar tive sanitizer (Inatsu et al, 2010b;Elano et al, 2010;Nei et al, 2009;Stopforth et al, 2008).…”