Evaluation of an Environmental Monitoring Program for the Microbial Safety of Air and Surfaces in a Dairy Plant Environment

Abstract

Microbiological hazards can occur when foodstuffs come into contact with contaminated surfaces or infectious agents dispersed by air currents in the manufacturing environment. An environmental monitoring program (EMP) is a critical aspect of sustainable and safe food manufacturing used to evaluate the effectiveness of the microbial controls in place. An effective EMP should be based on risk analysis, taking into account previous sampling history to determine the selection of the sampling points, the scope of the test, and the frequency of analysis. This study involved evaluation of the environmental monitoring regime and microbiological status of a medium-sized dairy plant manufacturing food ingredients, e.g., proteins, milk powders, and dairy fats. The data specific to microbial tests ( n = 3,468), recorded across 124 fixed sampling locations over a 2-year period (2014 to 2015) from air ( n = 1,787) and surfaces ( n = 1,681) were analyzed. The aim of this study was to highlight the strengths and weaknesses of the EMP in a select dairy processing plant. The results of this study outline the selection of sampling locations, the scope of the test, and the frequency of analysis. An analysis of variance revealed subsections of the manufacturing areas with high risk factors, especially the packaging subsection specified for bulk packaging, the atomizer, and the fluidized bed. The temporal and spatial analysis showed the potential to reduce or relocate the monitoring effort, most notably related to total coliforms and Staphylococcus aureus, across the dairy plant due to homogeneity across the sampling subsections with little or no deviations. The results suggest a need to reevaluate the current EMP and the corrective action plan, especially with regard to detection of pathogens. Recommendations for optimization of the EMP are presented to assist the dairy industry with reviewing and revising the control measures and hazard assessment with regard to existing contamination issues.

Monitoring environmental microbiological safety in a frozen fruit and vegetable plant

“…Overall, our data indicate that these were a significant reduction in the microorganism after the implementation of the EMP system. This is similar to findings by Zacharski et al (2018) that reported an environmental monitoring program plays an important role in the control of microbiological hazards in a dairy plant environment.…”

The Dairy Industry: Process, Monitoring, Standards, and Quality

“…Each step along the milk processing train can be contaminate by the air [74] and the water [75], used in the milk processing stages. Hygiene control at all stages, including hygienic design of the manufacturing equipment, is critically important.…”

Whole Genome-Based Characterization of Listeria monocytogenes Isolates Recovered From the Food Chain in South Africa

“…The adaptation and survival of L. monocytogenes in the food processing facilities occur mainly through their ability to proliferate in low temperature, pH and osmotic stress (Takahashi et al, 2014), as well as resistance to sanitation agents and formation of biofilm (Hurley et al, 2019). The control of L. monocytogenes in the food processing facilities is mostly based on application of quaternary ammonium compounds (QACs) biocides, such as BCs (Zacharski et al, 2018;Maury et al, 2019). However, the evolution of L. monocytogenes resistant to the BCs has been reported in several studies and has become a serious global concern (Zacharski et al, 2018;Korsak et al, 2019).…”

“…The control of L. monocytogenes in the food processing facilities is mostly based on application of quaternary ammonium compounds (QACs) biocides, such as BCs (Zacharski et al, 2018;Maury et al, 2019). However, the evolution of L. monocytogenes resistant to the BCs has been reported in several studies and has become a serious global concern (Zacharski et al, 2018;Korsak et al, 2019). These BC resistances are associated with several efflux resistance genes including bcrABC cassette, Ide, mdrL, qacH, qacA, qacE 1sul, and emrE which have been reported in various serotypes, ST and CC of L. monocytogenes isolated from diverse sources (Kovacevic et al, 2016;Korsak et al, 2019).…”