LISTERIA MONOCYTOGENES IN DELI MEATS AND WITHIN DRY BIOFILMS WITH PSEUDOMONAS AERUGINOSA AND SALMONELLA ENTERICA AND ENHANCING FOOD SAFETY RESEARCH OPPORTUNITIES FOR MINORITY SERVING INSTITUTIONS
Creators: name: Kaur, Gurpreet
Publisher: name: Purdue University Graduate School
Year: 2023
Subjects: Food safety, traceability, certification and authenticity
Microbiology not elsewhere classified
Research, science and technology policy

description: Unsafe food is responsible for causing more than 600 million cases of foodborne illnesses and 420,000 deaths each year. These foodborne illnesses have direct impact on growth and development in children, food and nutrition security, national economies, and sustainable development. Food manufactures, research institutions, governments, and consumers, together, play a pivotal role in establishing and implementing effective food safety systems. <em>Salmonella</em> spp. and <em>Listeria monocytogenes</em> are recognized as major threats to global food safety and security among other 31 known and unknown pathogens associated with foodborne illnesses and deaths. Since these pathogens can be transmitted through contaminated food and water, contaminated environmental surfaces, and subsequently from environment to food via cross-contamination, there is an urgent need for data-driven approaches to identify key points of contamination along the food systems to suggest interventions. While it is important to enhance food safety research in developed economies, developing capacity to enable conditions for food safety research translation and practice in developing economies is crucial for global food safety. In this dissertation, we presented three different research projects as summarized below- In Chapter 2 “Evaluating the efficacy of celery powder in ready-to-eat deli style turkey breast against <em>L. monocytogenes</em> under ideal and temperature abuse conditions”. In this study, we artificially inoculated “clean label” deli style turkey breast formulated with celery powder to evaluate the efficacy of this natural antimicrobial in inhibiting the growth of this pathogen. We stored the inoculated samples at ideal (4 °C) and abuse temperature conditions (7 °C, 10 °C, and 15 °C) for 21 d mimicking the possible temperature abuse along the cold chain, transportation, and at consumer refrigerator. Our findings indicated that although deli meat samples stored at 4 °C and 7 °C did not achieve significant growth of <em>L. monocytogenes;</em> increasing temperatures to 10 °C and 15 °C led to significant increase in the growth rate of this pathogen. This study evaluates the use and effectiveness of celery powder as an antimicrobial used by deli meat processors against <em>L. monocytogenes</em> in deli products. These data underscore the importance of maintaining refrigeration temperatures to complement the efficacy of antimicrobials. Chapter 3 “Investigating sanitary solutions to <em>L. monocytogenes, Salmonella enterica</em> ser. Typhimurium, and <em>Pseudomonas aeruginosa</em> dry surface biofilms”. In this study, we developed <em>in vitro</em> mono- and mix-culture dry surface biofilm (DSB) models of <em>L. monocytogenes, Salmonella enterica</em> ser. Typhimurium, and <em>Pseudomonas aeruginosa</em> leveraging the EPA MLB SOP MB-19 standard protocol using the CDC Biofilm Reactor and evaluated sanitation control strategies currently adopted by low-moisture food (LMF) food processors to determine their ability to inactive DSB, a decidedly difficult reservoir to eliminate. This study targets multiple biological hazards in a research area with very limited publicly available data and is the first of its kind to refine mono- and multi-species <em>in vitro</em> DSB models that mimic LMF facility conditions and combinations of relevant microorganisms for use cases (e.g., EPA adoption). The findings from this study indicated that these foodborne pathogens could form DSBs and serve as a source of pathogen reservoir and cross-contamination. Results from the efficacy testing of sanitizer and microfiber swabbing suggested that current sanitation practices may not be sufficient to remove or inactivate DSBs. This study will define future needs and new strategies to improve confidence in sanitation efficacy with private sector practitioners. Chapter 4 “Enhancing research for development opportunities for Minority Serving Institutions: a case study in food safety”. Most developing economies have limited viable food safety systems due to underdeveloped research capabilities, competing resource demands, and insufficient enabling conditions, which undermines food security. United States Minority Serving Institution (MSIs) researchers and outreach specialists are familiar with and arguably best positioned to address global food safety and security challenges and needs, but MSIs implement limited research for development programs (e.g., U.S. university-led Feed the Future (FTF) Innovation Labs (ILs) funded by the United States Agency for International Development (USAID)) aimed to solve these challenges. Recognizing this opportunity, the Feed the Future Innovation Lab for Food Safety (FSIL) led by Purdue University in partnership with Cornell University, created and implemented an MSI-led research partnerships for global food safety research programs. In this chapter, we put together the process of a three-stage Request for Applications (RFA) process, which included non-competitive and competitive stages to encourage partnership and to refine ideas. At the end of this process, seven individuals were invited to submit full proposals; two were funded. Intentional research opportunities and partnerships are essential to strengthen MSI competitiveness for research for development programs that develop and scale technologies to address urgent global agriculture, food security, and safety challenges.