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:
This article describes the basics of flow cytometry in its application to probiotic enumeration, including a comparison between flow cytometry and traditional plate count methods, afu vs cfu, advantages and disadvantages of flow cytometry, marketplace examples and investigative case studies.
This poster discusses research with the purpose of demonstrating a proof of concept for a reliable methodology evaluating postbiotic materials as characterized by inanimate cells by flow cytometry.
In a recent webinar, experts answered some FAQs about probiotic enumeration, with a focus on the applications of flow cytometry to probiotic products. This blog provides an overview of the questions and answers, including the benefits of flow cytometry, how it compares to plate counts, and considerations for testing.
Postbiotics are increasing in popularity, but are difficult to enumerate with traditional plating methods. Flow cytometry provides an avenue for measuring the dead or inactive cells in postbiotic products. This case study demonstrates how flow cytometry can assist with postbiotic enumeration when plate methods result in low cell counts.
This informative blog post covers the basics of probiotic testing for new brands. Learn about federal regulations, formulation, and testing options, including plate counts and flow cytometry, surrounding the efficacy and safety of probiotic supplements. This article contains valuable information for anyone involved in probiotic manufacturing, formulation, or branding!
If you are a manufacturer or sell probiotic supplements, testing for counts of probiotic strains is not always straight forward. Here are five tips you should know when it comes to testing your product and verifying your label claims.
Testing or enumeration Bacillus coagulans in gummies is not as straight forward as it seems. Sometimes product matrices are challenging and require a new custom method. Learn how our testing experts know exactly how to problem solve testing in tough matrices like gummy candies.
If you have been using an established probtioic enumeration method with good results, introducing new probiotic strains into your formulas may mean changes need to be made. Read this case study to learn how Eurofins finds a solution to challenging product with multiple strains from multiple manufacturers.
Is your probiotic supplement formulated with both probiotic bacteria and active compounds? If so, getting accurate enumeration of probiotic strains can be a challenge. Learn how our experts in probiotic testing are skilled in finding solutions to tough probiotic formulations in this case study.
Method validation, method verification and fitness for purpose all seem similar, but each requires a distinct level of evaluation and different considerations. Learn more about their similarities and differences in this article.
