Comparison of the disinfection efficacy of chlorine-based products for inactivation of viral indicators and pathogenic bacteria in produce wash water

Abstract

Outbreaks of pathogenic bacteria infections associated with the consumption of fresh produce has occurred with increased frequency in recent years. This study was undertaken to determine the efficacy of three commonly used disinfectants in packing-houses of Culiacan, Mexico (sodium hypochlorite [NaOCl], trichlor-s-triazinetrione [TST] and thrichlormelamine [TCM]) for inactivation of viral indicators and pathogenic bacteria inoculated onto produce wash water. Each microbial challenge consisted of 2 L of water containing approximately 8 log10 bacterial CFU ml(-1), and 8 log10 viral PFU ml(-1) treated with 100 and 300 mg l(-1) of total chlorine with modified turbidity. Water samples were taken after 2 min of contact with chlorine-based products and assayed for the particular microorganisms. TST and NaOCl were found to effectively reduce for bacterial pathogens and viral indicators 8 log10 and 7 log10, respectively (alpha=0.05). The highest inactivation rate was observed when the turbidity was low and the disinfectant was applied at 300 mg l(-1). TCM did not show effective results when compared with the TST and NaOCl (P<0.05). These findings suggest that turbidity created by the organic and inorganic material present in the water tanks carried by the fresh produce may affect the efficacy of the chlorine-based products.

Efficacy of Chlorine, Chlorine Dioxide, and Peroxyacetic Acid in Reducing Salmonella Contamination in Wash Water and on Mangoes Under Simulated Mango Packinghouse Washing Operations

“…These parameters primarily reduce the residual concentration of the disinfectant and therefore reduce its antimicrobial activity over time. In effect, studies have demonstrated that there is an inverse relationship between antimicrobial efficacy and organic load (Chaidez et al, 2003;López-Gálvez et al, 2009;Meireles et al, 2016). Similar to these findings, we observed a significant reduction in disinfectant over time, particularly in the hot water tank and in the presence of organic contamination ( Figure S2).…”

Salmonella and produce: Survival in the plant environment and implications in food safety

“…The potential contamination of produce is possible during cultivation, handling, processing and preparation of the products as illustrated in previous produce-associated outbreaks. 11,33,34 Once Salmonella spp has attached to the produce, the pathogen may sustain throughout the shelf life of the product. Salmonella spp have been isolated from both red and green tomatoes as well as sprouts, mangoes, peppers and cantaloupes.…”

Salmonella and Tomatoes

“…A study was undertaken by Chaidez et al (2003) to determine the efficacy of three commonly used disinfectants in packinghouses of Sinaloa, Mexico: sodium hypochlorite (NaOCl), trichlor-s-triazinetrione (TST), and trichlormelamine (TCM). Even though TST is approved only for swimming pool area disinfection, sometimes it is used for application to produce contact surfaces in Mexico.…”