J. David Legan, PhD
Director of Science
David earned his Ph.D. in Food Technology from the University of Reading in the UK by modeling the ecology of mixed microbial populations, and then moved to Campden BRI in a variety of microbiological food safety research and client service roles. During that time, he was project lead for the Bacillus component of the UK’s pathogen modeling program. He moved again to Nabisco Research in New Jersey where he ran the corporate microbiology lab and developed a program of preservation technology development and microbial modeling. After the Kraft Foods acquisition, he moved to Chicago to work on Food Safety and Preservation research, and through modeling and validation studies:
- Optimized Oscar Mayer’s use of lactate and diacetate and their naturally cultured alternatives as Listeria-control agents in Ready to Eat meats
- Specified process conditions central to Oscar Mayer’s commercial launch of High Pressure Pasteurization of naturally cured RTE meats
David had responsibility for the Kraft cultures R&D group, developed a partnership to explore microwave sterilization leading to several patents, and led a program that developed an internal proprietary natural antimicrobial commercialized in several Kraft products. Technologies from his group supported approximately $4 billion in annual sales.
After years as a microbiology "client", he is now back in the "provider" role as Director of Science at Eurofins Microbiology Laboratories, Inc., by way of the Covance Food Solutions group based in Madison, WI, which he joined in 2016. In this role, he ensures appropriate method validation, explores new testing technologies, and fields multiple complicated food microbiology questions.
Products that his team has evaluated or developed and launched include:
- The 3M MDS platform in the Madison microbiology laboratory
- Flow cytometry for enumeration of probiotics
- Strain-level confirmation of probiotic identification using the polymerase chain reaction (PCR)
- Next-generation sequencing using the Oxford Nanopore Technologies GridION sequencing platform for microbial identification and microbiome analysis
Below are resources from David:
Why was the genus Lactobacillus reclassified? Andrzej Benkowski, Technical Leader from Eurofins Microbiology in Madison, WI discusses this topic in this short video. Eurofins publishes our Ask an Expert Series weekly on our social media platforms.
Bacillus consists of a wide range of species from pathogenic types to beneficial bacteria. Bacillus coagulans, specifically, is commonly used in various products due to its survivability of many processing conditions as well as long shelf life needs. So, how would you test for the pathogen, Bacillus cereus, in a product containing Bacillus coagulans? Our Principle Scientist, Megan Brown, discussed more on this topic and what to keep in mind.
Read about the function of probiotics in the body, the different varieties and benefits, and how they’re consumed in the diet, from common to new sources. See what to consider when choosing a third party lab for testing and how Eurofins is one of the most trusted labs in the industry.
In this presentation, USP and Eurofins Microbiology provided an overview of USP microbiology methods tests for microbial contamination in dietary supplements, CBD/hemp products, and probiotics. The session included an in-depth discussion regarding the importance of suitability testing, and a comparison of USP methodology to AOAC/FDA BAM methodology. USP also provided an update on new USP chapters and shared insight on what is on the horizon for USP methods.
DNA sequencing is an important tool to identify all Probiotic organisms in a sample all in one assay. In this Scientific Poster, Eurofins scientists investigate a long-read sequencing method that accurately identifies probiotic organisms in complex samples recently presented at SHIFT 20.
In this poster, Eurofins describes how the utility of flow cytometry was expanded further by applying modifications to ISO 19344(B) in order to accurately quantify the yeast in the sample.
This scientific poster demonstrates how flow cytometry can be used to accurately and precisely enumerate B. coagulans and B. subtilis in a gummy matrix.
Our objective was to compare the efficacy of commercially available pathogen screening platforms for detecting Salmonella in probiotic cultures to permit evidence-based platform selection.
This study seeks to establish the detectability of Listeria species in probiotic cultures and estimate the sensitivity of detection.
Enumeration provides the most basic required information with methodologies evolving to provide improved accuracy, precision, and turnaround times. Acoustic-assisted hydrodynamic flow cytometry incorporates the advance of using sound waves to align the particles in the fluid stream for counting, reducing the time to result.