About

Kathryn Jean Boor is a Professor of Food Processing Microbiology at Cornell University. Her previous research focused on identifying biological factors that affect the transmission of bacteria in food systems, from farm to table. She established the Food Safety Laboratory at Cornell University and directed the Milk Quality Improvement Program; her group published more than 175 peer-reviewed manuscripts. Among her notable discoveries, her team identified seminal evidence linking bacterial environmental stress response with virulence gene expression in the foodborne pathogen, Listeria monocytogenes. Dr. Boor earned a BS in Food Science from Cornell University, an MS in Food Science from the University of Wisconsin, and a PhD in Microbiology from the University of California, Davis. She joined the Cornell Food Science department as an assistant professor in 1994, became its first tenured female faculty member in 2000, and served as department chair from 2007 to 2010. She has held leadership roles including Dean of the College of Agriculture and Life Sciences at Cornell and Dean of the Graduate School and Vice Provost for Graduate Education. Dr. Boor serves on multiple boards, including Seneca Foods Corporation, International Flavors and Fragrance, and Sarepta Therapeutics, and has served on various national and state committees related to food safety and agricultural research. She is a Fellow of several prestigious organizations, including the American Academy of Microbiology, the International Academy of Food Science and Technology, and the American Association for the Advancement of Science. Her honors include an honorary doctorate from Harper Adams University and recognition as a Woman of Distinction by the New York State Senate.

Research topics

• Biology
• Machine Learning
• Computer Science
• Genetics
• Environmental science
• Food science
• Statistics
• Operations management
• Molecular biology
• Engineering
• Environmental economics
• Mathematics

Selected publications

• 12. Tests for Groups of Microorganisms

  American Public Health Association eBooks · 2024 · 78 citations

  1st authorCorresponding
  • Environmental science
  • Biology
  • Genetics
  PublisherDOI

• Machine Learning and Advanced Statistical Modeling Can Identify Key Quality Management Practices That Affect Postpasteurization Contamination of Fluid Milk

  Journal of Food Protection · 2021 · 28 citations

  • Computer Science
  • Machine Learning
  • Operations management
  PublisherDOI

• Transcriptional profiling of the<i>L. monocytogenes</i>PrfA regulon identifies six novel putative PrfA-regulated genes

  FEMS Microbiology Letters · 2020 · 22 citations

  • Biology
  • Genetics
  • Molecular biology

  The transcriptional activator Positive Regulatory Factor A (PrfA) regulates expression of genes essential for virulence in Listeria monocytogenes. To define the PrfA regulon, the 10403S wildtype (WT) strain, a constitutively active prfA* mutant, and an isogenic ∆prfA mutant were grown under PrfA-inducing conditions in a medium containing glucose-1-phosphate and pre-treated with 0.2% activated charcoal. RNA-seq-generated transcript levels were compared as follows: (i) prfA* and WT; (ii) WT and ∆prfA and (iii) prfA* and ∆prfA. Significantly higher transcript levels in the induced WT or constitutively active PrfA* were identified for 18 genes and 2 ncRNAs in at least one of the three comparisons. These genes included: (i) 10/12 of the genes previously identified as directly PrfA-regulated; (ii) 2 genes previously identified as PrfA-regulated, albeit likely indirectly; and (iii) 6 genes newly identified as PrfA-regulated, including one (LMRG_0 2046) with a σA-dependent promoter and PrfA box located within an upstream open reading frame. LMRG_0 2046, which encodes a putative cyanate permease, is reported to be downregulated by a σB-dependent anti-sense RNA. This newly identified overlap between the σB and PrfA regulons highlights the complexity of regulatory networks important for fine-tuning bacterial gene expression in response to the rapidly changing environmental conditions associated with infection.

  PublisherDOI

• A practical training program for fluid milk defect judging should focus on initial training of panelists

  Journal of Dairy Science · 2020-04-22 · 4 citations

  articleOpen access

  The sensory quality of fluid milk is of great importance to processors and consumers. Defects in the expected odor, flavor, or body of the product can affect consumer attitudes toward the product and, ultimately, willingness to purchase the product. Although many methods of sensory evaluation have been developed, defect judging is one particular method that has been used for decades in the dairy industry for evaluating fluid milk. Defect judging is a technique whereby panelists are trained to recognize and rate a standard set of fluid milk defects that originate from various sources (e.g., microbial spoilage). This technique is primarily used in processing facilities where identification of sensory defects can alert personnel to potential quality control issues in raw material quality, processing, or good manufacturing practices. In 2014-2016, a preliminary study of defective milk judging screening and training was conducted by the Milk Quality Improvement Program at Cornell University (Ithaca, NY). The study, which included 37 staff and students from the Cornell community, used prescreenings for common odors and basic tastes, followed by uniform training to select, initially train, and retrain defect judges of unflavored high temperature, short time fluid milk. Significant improvements were seen in correct identification of defect attributes following initial training for all defect attributes, with the exception of fruity/fermented. However, following retraining, significant improvements were observed in only 2 defect attributes: cooked and milk carton. These results demonstrate that initial training is important for panelists to correctly identify fluid milk defect attributes, but that subsequent retraining should be tailored toward specific attributes. This study provides a resource for dairy industry stakeholders to use to develop relevant and efficient training methods for fluid milk defect judging panels.

  PublisherOA PDFDOI

• Cross Talk between SigB and PrfA in Listeria monocytogenes Facilitates Transitions between Extra- and Intracellular Environments

  Microbiology and Molecular Biology Reviews · 2019-09-03 · 82 citations

  reviewOpen accessSenior author

  The foodborne pathogen Listeria monocytogenes can modulate its transcriptome and proteome to ensure its survival during transmission through vastly differing environmental conditions.

  PublisherOA PDFDOI

• Scientific Integrity Principles and Best Practices: Recommendations from a Scientific Integrity Consortium

  Science and Engineering Ethics · 2019-02-27 · 170 citations

  articleOpen access

  A Scientific Integrity Consortium developed a set of recommended principles and best practices that can be used broadly across scientific disciplines as a mechanism for consensus on scientific integrity standards and to better equip scientists to operate in a rapidly changing research environment. The two principles that represent the umbrella under which scientific processes should operate are as follows: (1) Foster a culture of integrity in the scientific process. (2) Evidence-based policy interests may have legitimate roles to play in influencing aspects of the research process, but those roles should not interfere with scientific integrity. The nine best practices for instilling scientific integrity in the implementation of these two overarching principles are (1) Require universal training in robust scientific methods, in the use of appropriate experimental design and statistics, and in responsible research practices for scientists at all levels, with the training content regularly updated and presented by qualified scientists. (2) Strengthen scientific integrity oversight and processes throughout the research continuum with a focus on training in ethics and conduct. (3) Encourage reproducibility of research through transparency. (4) Strive to establish open science as the standard operating procedure throughout the scientific enterprise. (5) Develop and implement educational tools to teach communication skills that uphold scientific integrity. (6) Strive to identify ways to further strengthen the peer review process. (7) Encourage scientific journals to publish unanticipated findings that meet standards of quality and scientific integrity. (8) Seek harmonization and implementation among journals of rapid, consistent, and transparent processes for correction and/or retraction of published papers. (9) Design rigorous and comprehensive evaluation criteria that recognize and reward the highest standards of integrity in scientific research.

  PublisherOA PDFDOI

• Systematic Review of the <i>Listeria Monocytogenes</i> σ ^B Regulon Supports a Role in Stress Response, Virulence and Metabolism

  Future Microbiology · 2019-06-01 · 94 citations

  reviewOpen access

  Aim: Among the alternative sigma factors of Listeria monocytogenes, B controls the largest regulon. The aim of this study was to perform a comprehensive review of B -regulated genes, and the functions they confer. Materials & methods: A systematic search of PubMed and Web of Knowledge was carried out to identify members of the B regulon based on experimental evidence of B -dependent transcription and presence of a consensus B -dependent promoter. Results: The literature review identified B -dependent transcription units encompassing 304 genes encoding different functions including stress response and virulence. Conclusion: Our review supports the well-known roles of B in virulence and stress response and provides new insight into novel roles for B in metabolism and overall resilience of L. monocytogenes.

  PublisherOA PDFDOI

• The Listeria monocytogenes Bile Stimulon under Acidic Conditions Is Characterized by Strain-Specific Patterns and the Upregulation of Motility, Cell Wall Modification Functions, and the PrfA Regulon

  Frontiers in Microbiology · 2018-02-06 · 29 citations

  articleOpen accessSenior authorCorresponding

  Listeria monocytogenes uses a variety of transcriptional regulation strategies to adapt to the extra-host environment, the gastrointestinal tract, and the intracellular host environment. While the alternative sigma factor SigB has been proposed to be a key transcriptional regulator that facilitates Listeria monocytogenes adaptation to the gastrointestinal environment, the L. monocytogenes’ transcriptional response to bile exposure is not well understood. RNA-seq characterization of the bile stimulon was performed in two L. monocytogenes strains representing lineages I and II. Exposure to bile at pH 5.5 elicited a large transcriptomic response with approx. 16% and 23% of genes showing differential transcription in 10403S and H7858, respectively. The bile stimulon includes genes involved in motility and cell wall modification mechanisms, as well as genes in the PrfA regulon, which likely facilitate survival during the gastrointestinal stages of infection that follow bile exposure. The fact that bile exposure induced the PrfA regulon, but did not induce further upregulation of the SigB regulon (beyond that expected by exposure to pH 5.5), suggests a model where at the earlier stages of gastrointestinal infection (e.g., acid exposure in the stomach), SigB-dependent gene expression plays an important role. Subsequent exposure to bile induces the PrfA regulon, potentially priming L. monocytogenes for subsequent intracellular infection stages. Some members of the bile stimulon showed lineage- or strain-specific distribution when 27 Listeria genomes were analyzed. Even though sigB null mutants showed increased sensitivity to bile, the SigB regulon was not found to be upregulated in response to bile beyond levels expected by exposure to pH 5.5. Comparison of wildtype and corresponding ΔsigB strains newly identified 26 SigB-dependent genes, all with upstream putative SigB-dependent promoters.

  PublisherDOI

• Psychrotolerant spore-former growth characterization for the development of a dairy spoilage predictive model

  Journal of Dairy Science · 2018-05-24 · 43 citations

  articleOpen access

  Psychrotolerant spore-forming bacteria represent a major challenge regarding microbial spoilage of fluid milk. These organisms can survive most conventional pasteurization regimens and subsequently germinate and grow to spoilage levels during refrigerated storage. To improve predictions of fluid milk shelf life and assess different approaches to control psychrotolerant spore-forming bacteria in the fluid milk production and processing continuum, we developed a predictive model of spoilage of fluid milk due to germination and growth of psychrotolerant spore-forming bacteria. We characterized 14 psychrotolerant spore-formers, representing the most common Bacillales subtypes isolated from raw and pasteurized milk, for ability to germinate from spores and grow in skim milk broth at 6C. Complete growth curves were obtained by determining total bacterial count and spore count every 24 h for 30 d. Based on growth curves at 6C, probability distributions of initial spore counts in bulk tank raw milk, and subtype frequency in bulk tank raw milk, a Monte Carlo simulation model was created to predict spoilage patterns in high temperature, short time-pasteurized fluid milk. Monte Carlo simulations predicted that 66% of half-gallons (1,900 mL) of high temperature, short time fluid milk would reach a cell density greater than 20,000 cfu/mL after 21 d of storage at 6C, consistent with current spoilage patterns observed in commercial products. Our model also predicted that an intervention that reduces initial spore loads by 2.2 Log 10 most probable number/mL (e.g., microfiltration) can extend fluid milk shelf life by 4 d (end of shelf life was defined here as the first day when the mean total bacterial count exceeded 20,000 cfu/mL). This study not only provides a baseline understanding of the growth rates of psychrotolerant spore-formers in fluid milk, it also provides a stochastic model of spoilage by these organisms over the shelf life of fluid milk, which will ultimately allow for the assessment of different approaches to reduce fluid milk spoilage.

  PublisherOA PDFDOI

• Pseudomonas fluorescens group bacterial strains are responsible for repeat and sporadic postpasteurization contamination and reduced fluid milk shelf life

  Journal of Dairy Science · 2018-06-28 · 67 citations

  articleOpen access

  Postpasteurization contamination (PPC) of high temperature, short time-pasteurized fluid milk by gram-negative (GN) bacteria continues to be an issue for processors. To improve PPC control, a better understanding of PPC patterns in dairy processing facilities over time and across equipment is needed. We thus collected samples from 10 fluid milk processing facilities to (1) detect and characterize PPC patterns over time, (2) determine the efficacy of different media to detect PPC, and (3) characterize sensory defects associated with PPC. Specifically, we collected 280 samples of high temperature, short time-pasteurized milk representing different products (2%, skim, and chocolate) and different fillers over 4 samplings performed over 11 mo at each of the 10 facilities. Standard plate count (SPC) as well as total GN, coliform, and Enterobacteriaceae (EB) counts were performed upon receipt and after 7, 10, 14, 17, and 21 d of storage at 6°C. We used 16S rDNA sequencing to characterize representative bacterial isolates from (1) test days with SPC >20,000 cfu/mL and (2) all samples with presumptive GN, coliforms, or EB. Day-21 samples were also evaluated by a trained defect judging panel. By d 21, 226 samples had SPC >20,000 cfu/mL on at least 1 d of shelf life; GN bacteria were found in 132 of these 226 samples, indicating PPC. Crystal violet tetrazolium agar detected PPC with the greatest sensitivity. Spoilage due to PPC was predominantly associated with Pseudomonas (isolated from 101 of the 132 samples with PPC); coliforms and EB were found in 27 and 37 samples with spoilage due to PPC, respectively. Detection of Pseudomonas and Acinetobacter was associated with lower flavor scores; coagulated, fruity fermented, and unclean defects were more prevalent in d-21 samples with PPC. Repeat isolation of Pseudomonas fluorescens group strains with identical partial 16S rDNA sequence types was observed in 8 facilities. In several facilities, specific lines, products, or processing days were linked to repeat product contamination with Pseudomonas with identical sequence types. Our data show that PPC due to Pseudomonas remains a major challenge for fluid milk processors; the inability of coliform and EB tests to detect Pseudomonas may contribute to this. Our data also provide important initial insights into PPC patterns (e.g., line-specific contamination), supporting the importance of molecular subtyping methods for identification of PPC sources.

  PublisherOA PDFDOI

Recent grants

• NIH Grant R01AI052151

  NIH · $2.7M · 2014

Frequent coauthors

• Ronald Richter

  Rutgers, The State University of New Jersey

  144 shared

• Martin Wiedmann

  Cornell University

  129 shared

• Ellen Jordan

  Cornell University

  72 shared

• D.J. Schingoethe

  72 shared

• J.W. Fuquay

  Mississippi State University

  72 shared

• John C. Bruhn

  Mississippi State University

  72 shared

• Harold E. Swaisgood

  72 shared

• David A. Henning

  Michigan State University

  72 shared

Awards & honors

• Research Award in Dairy Foods Processing
• Honorary Doctorate 2016 Harper Adams University, United King…
• Cap Creal Journalism Award for best printed editorial 2015 N…
• Emmett R. Gauhn Memorial Award 2012 New York State Associati…
• David K. Bandler Cheese Industry Award 2011 New York State C…