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3-A SSI awarded eight dedicated food safety students with a Dr. Ron Schmidt Student Travel Award in 2025. These talented students attended the 3-A annual conference, presenting poster sessions on their areas of study. In the coming months, we’ll share their research in the 3-A SSI Blog.
This week, work by Karen Nieto Flores, a PhD candidate at the University of Nebraska-Lincoln is featured. Flores is one of several recipients of the 2025 3-A award to be featured in the September newsletter of Phi Tau Sigma: The Honor Society of Food Science and Technology. Her research evaluates the effectiveness of cleaning and sanitizing procedures for Listeria in dairy processing environments, with special focus on personal protective equipment as a potential vector for contamination.
Karen Nieto Flores1, Aryany Pena Gomez1,Ilhami Okur1, Jayne Stratton1,2, Bing Wang1,Andreia Bianchini1,2*
1Department of FoodScience & Technology, University of Nebraska, Lincoln, NE, USA
2 The Food Processing Center, University of Nebraska-Lincoln. Lincoln, NE68588, USA
Highlights
Most of the included studies (73%) assessed log reductions on stainless steel surfaces, with fewer studies evaluating plastics, highlighting a data gap on sanitizer effectiveness on these materials.
ABSTRACT
Listeria presents persistent challenges for dairy manufacturers due to its ability to thrive in the processing environment and resist sanitation efforts. Despite studies examining effective sanitizing interventions, the need for a comprehensive and critical evaluation of the intervention efficacies arises, given the variations in study size and design, microbial persistence, and tolerance to sanitizers. Therefore, a systematic review was conducted to identify, appraise, and synthesize information on effective sanitation interventions for Listeria spp. across diverse surfaces in a dairy plant setting. Six electronic bibliographic databases were searched using terms that reflected four concepts: intervention strategies, Listeria spp. log reduction, surfaces, and dairy environment. The initial literature search yielded 4,677 records. After the title/abstract-based and full text-based screening, data were extracted from 50 unique records for further analysis. Results showed that Listeria inactivation through sanitizers resulted in median log reductions ranging from 2.12 to 3.63 log CFU/cm2, with peroxyacetic acid sanitizers achieving the highest efficacy. Regarding the physiological state of Listeria spp., 74% of the studies investigated Listeria monocytogenes in biofilm form, while 18% focused on planktonic stages. Chlorine-based sanitizers were the most frequently studied, followed by quaternary ammonium compounds and peroxyacetic acid sanitizers. Most of the included studies (73%) assessed log reductions on stainless steel surfaces, with fewer studies evaluating plastics, highlighting a data gap on sanitizer effectiveness on these materials. The present study synthesized quantitative evidence to enhance understanding of the effectiveness of sanitation interventions in controlling Listeria spp., providing insights into sanitation practices that should be followed within dairy processing environments.
Keywords: Dairy Foods; Listeria, Biofilm, Sanitizers, Food-Contact Surfaces, Systematic Review
Do you know a student in food safety, equipment design or a related field? The application for the Dr. Ron Schmidt Student Travel Award is available now on the new 3-A SSI Student resources page. In addition to information on the award, the page includes curated resources to help students build their expertise and launch a career in food safety and equipment design.
We're taking the value of 3-A certification directly to buyers at PACK EXPO, September 29 to October 1 in Las Vegas. Whether they’re attending our session or roaming the exhibit hall, we want to give attendees concrete reasons to choose equipment bearing the 3-A Symbol.
The 3-A Sanitary Standards, Inc. (3-A SSI) headquarters is moving to a new location in Washington, DC. The move will better serve our mission and the 3-A SSI community and will be complete on Monday, August 25, 2025.
3-A SSI awarded eight dedicated food safety students with a Dr. Ron Schmidt Student Travel Award.
While participating in IAFP’s Professional Development Group (PDG) meetings, 3-A learned there is a strong interest in hygienic design training amongst food safety professionals and regulators.
