Analyzing aggregate environmental monitoring data for Listeria spp. in frozen food manufacturing environments

• Published in: Food control 2022-05, Vol.135, p.108746, Article 108746
• Main Authors: Magdovitz, Brittany F., Gummalla, Sanjay, Garren, Donna, Thippareddi, Harshavardhan, Berrang, Mark E., Love, Kim, Harrison, Mark A.
• Format: Article
• Language: English
• Subjects: Frozen food; Listeria monocytogenes; Listeria spp
• ISSN: 0956-7135; 1873-7129
• DOI: 10.1016/j.foodcont.2021.108746

Food processors face serious challenges due to the ubiquity and prevalence of Listeria monocytogenes in production and processing facilities. Environmental monitoring for Listeria within the industry is important and detection of Listeria spp. is often used as an indicator for the potential presence of L. monocytogenes in the food processing environment. Environmental monitoring data from the frozen food manufacturing industry was compiled and analyzed to evaluate the adequacy of current practices in mitigating risks of L. monocytogenes in the processing environment and to determine if there are trends that could be used to further refine industry practices. A method to collect anonymous data for analysis to build a strong aggregate data set from multiple facilities was used. Information included general descriptions of each facility and specific information about individual environmental monitoring test results from environmental zones 2–4, or nonfood contact surfaces. Information collected from facilities included the size of the facilities and how environmental monitoring samples were collected and analyzed. For each individual sample, information collected included the area or equipment sampled and the result of each sample. Descriptors were provided to allow for grouping of similar results. The data represents environmental monitoring samples that were collected between six months to a year prior to the beginning of this research. Twenty-seven facilities provided 42,799 environmental monitoring observations. Environmental zones 3 and 4 had a higher estimated marginal probability of Listeria positive results compared to zone two for routine environmental monitoring samples (p