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Dr Michael Callanan

education and career profile

Nestlé R&D, Switzerland. 2010-2015

Established and managed a research program consisting of multiple internal and external projects on product innovation and rennovation. Portfolio of projects included Strategic Business Unit and corporate briefed R&D projects involving both internal and external research centers.

Glanbia Nutritionals. 2007– 2009
Research scientist with responsibility for research and development of a range of Glanbia Nutritionals bioactive ingredients.

Teagasc, Moorepark Food Research Centre. 2002-2007
Research Officer responsible for a research program focused on the identification and characterization of novel enzymes for food and health applications.

North Carolina State University, U.S.A. 1999-2002
Postdoctoral research fellow responsible for managing a research project investigating the externalization of recombinant enzymes from probiotic cultures.


Massey University, New Zealand. 1997-1999

Postdoctoral research fellow responsible for managing a research project within the starter cultures research unit of Fonterra Cooperative Group Ltd.


Research interests

Food quality and safety microbiology, predictive microbiology, product innovation and renovation from concept through to market launch. Industrial experience in alternative ingredient and process development for multiple products (infant formula, protein supplements, RTD beverages and healthcare nutrition) at Nestlé Research Centre, Switzerland and Glanbia Nutritionals Ireland.


Ongoing research 

  • CIT RISAM PhD Scholarship Scheme. Assessment of mathematical models to predict the growth of bacteria in re-formulated foods.
  • Department of Agriculture FIRM 15F604. Thermal or Membrane Infant formula.
  • Teagasc Walsh Fellowship. Biotransformation of whole milk powder and its derivatives for the generation of natural dairy flavours.


  • Nyhan L, Begley M, Mutel A, Qu Y, Johnson N, Callanan, M. (2018) Predicting the combinatorial effects of water activity, pH and organic acids on Listeria growth in media and complex food matrices. Food microbiology 74 p74-85
  • De Bruyn F, Zhang S, Pothakos V, Torres J, Lambot,C, Moroni A, Callanan M, Sybesma W, Weckx S, De Vuyst L. (2017) Exploring the impacts of postharvest processing on the microbiota and metabolite profiles during green coffee bean production. Applied and Environmental Microbiology 83 p2398-16
  • Guinane C and Callanan M (2017) Genome Sequencing of Microbes. Life Sciences
  • Georget E, Kushman A, Callanan M, Ananta E, Heinz V, Mathys A.  (2015) Geobacillus stearothermophilus ATCC 7953 spore chemical germination mechanisms in model systems. Food Control. 50 p141-149
  • Georget E, Sevenich R, Reineke K, Mathys A, Heinz V, Callanan M, Rauh C, Knorr D. (2015) Inactivation of microorganisms by high isostatic pressure processing in complex matrices: A review. Innovative Food Science & Emerging Technologies 27 p1-14
  • Johnson N, Chang Z, Almeida C Bravo, Michel M, Iversen C, Callanan M (2014) Evaluation of indirect impedance for measuring microbial growth in complex food matrices Food Microbiology 42 p8-13
  • Georget E, Miller B, Callanan M, Heinz V, Mathys A. (2014) (Ultra) High Pressure Homogenization for Continuous High Pressure Sterilization of Pumpable Foods–A Review. Frontiers in Nutrition 1 p15
  • Georget E, Miller B, Aganovic K, Callanan M, Heinz V, Mathys A. (2014) Bacterial spore inactivation by ultra-high pressure homogenization. Innovative Food Science & Emerging Technologies 26 p116-123
  • Coffey B, Ross P, O'Flynn G, O'sullivan O, Casey A, Callanan M, Coffey A, McAuliffe O. (2014) Complete genome sequence of vB_EcoM_112, a T-even-type bacteriophage specific for Escherichia coli O157: H7 Genome announcements 2 p293-4
  • Georget E, Kapoor S, Winter R, Reineke K, Song Y, Callanan M, Ananta E, Heinz V, Mathys A. (2014) In situ investigation of Geobacillus stearothermophilus spore germination and inactivation mechanisms under moderate high pressure. Food Microbiology 41 p8-18
  • Callanan M, Paes M, Iversen C, Kleijn R,  Almeida Bravo C, Peñaloza W, Johnson N, Vuataz G, Michel M. (2012) Behavior of Enterobacter pulveris in amorphous and crystalline powder matrices treated with supercritical carbon dioxide. Journal of Dairy Science 95 p6300-6306
  • Bahar B, O’Halloran F, Callanan M, McParland S, Giblin L, Sweeney T. (2011) Bovine lactoferrin (LTF) gene promoter haplotypes have different basal transcriptional activities. Animal Genetics 42 p270-279
  • Giblin L, Butler S, Kearney B, Waters S, Callanan M, Berry D (2010) Association of bovine leptin polymorphisms with energy output and energy storage traits in progeny tested Holstein-Friesian dairy cattle sires. BMC Genetics 11 p73
  • O'Sullivan O, O'Callaghan J, Sangrador-Vegas A, McAuliffe O, Slattery L, Kaleta P, Callanan M, Fitzgerald GF, Ross P, Beresford T (2009) Comparative genomics of lactic acid bacteria reveals a niche-specific gene set. BMC Microbiology 9 p50
  • Kaleta P, Callanan M, O'Callaghan J, Fitzgeraald G, Beresford T, Ross P (2009) Exploitation of the diverse insertion sequence element content of dairy Lactobacillus helveticus starters as a rapid method to identify different strains. Journal of Microbiological Methods 79 p32-36
  • Callanan M, Kaleta P, O'Callaghan J, O'Sullivan O, Jordan K, McAuliffe O, Sangrador-Vegas A, Slattery L, Fitzgerald GF, Beresford T (2008) Genome sequence of Lactobacillus helveticus, an organism distinguished by selective gene loss and insertion sequence element expansion. Journal of Bacteriology 190 p 727-735
  • Callanan M and Klaenhammer TR (2008) Bacteriophage in Industry (2nd edition). Encyclopedia of Life Sciences. Macmillan Reference Ltd., Nature Publishing Group, London, UK. Available at
  • O’Connor EB, O’Sullivan O, Stanton C, Danielsen M, Simpson PJ, Callanan M, Ross RP, Hill C. (2007) pEOC01: a plasmid from Pediococcus acidilactici which encodes an identical streptomycin resistance (aadE) gene to that found in Campylobacter jejuni. Plasmid 58 p115-126
  • Callanan M, Ross RP, Beresford T. (2007) Insertion sequence elements as mediators of strain diversity in Lactobacillus helveticus. International Journal of Food Microbiology 120 p120-123
  • Callanan M, Russell WM, Klaenhammer TR. (2007) Modification of Lactobacillus β-glucuronidase activity by random mutagenesis. Gene 389 p122-127
  • Trotter M, McAuliffe O, Callanan M, Edwards R, Fitzgerald GF, Coffey A, Ross P.  (2006) Genome analysis of the obligately lytic bacteriophage 4268 of Lactococcus lactis provides insight into its adaptable nature. Gene 366 p189-199
  • Altermann E, Russell WM, Azcarate-Peril A, Barrangou R, Buck BL, McAuliffe O, Souther N, Dobson A, Duong T, Callanan M, Lick S, Hamrick A, Cano R, Klaenhammer TR. (2005) Complete genome sequence of the probiotic lactic acid bacterium Lactobacillus acidophilus NCFM. Proceedings of the National Academy of Sciences 102 p 3906-3912
  • Callanan M (2005) Mining the probiotic genome: advanced strategies, enhanced benefits, perceived obstacles. Current Pharmaceutical Design 11 p25-36
  • Callanan M, Beresford T, Ross RP. (2005)  Genetic diversity in the lactose operons of Lactobacillus helveticus strains and its relationship to the role of these strains as commercial starter cultures. Applied and Environmental Microbiology 71 p1655-8
  • Schiemann A, Rakonjac J, Callanan M, Gordon J, Polzin K, Lubbers M, O'Toole P. (2004) Essentiality of the early transcript in the replication origin of the lactococcal prolate phage c2 Journal of Bacteriology 186 p8010-7
  • Callanan M and Ross RP (2004) Starter cultures: Genetics. In Cheese; Chemistry, Physics and Microbiology (3rd edition) Vol 1 p149-61. Elsevier Publishers, London.
  • Tuler TR, Callanan M, Klaenhammer TR. (2002) Overexpression of peptidases in Lactococcus and evaluation of their release from leaky cells Journal of Dairy Science 85 p2438-50
  • Callanan M, O'Toole P, Lubbers M, Polzin K. (2001) Examination of lactococcal bacteriophage c2 DNA replication using two-dimensional agarose gel electrophoresis. Gene 278 p101-106
  • Callanan M and Klaenhammer TR (2001) Bacteriophage in Industry. Encyclopedia of Life Sciences. Macmillan Reference Ltd., Nature Publishing Group, London, UK. Available at
  • Callanan M, Sexton R, Dowling DN, O'Gara Fergal. (1996) Regulation of the iron uptake genes in Pseudomonas fluorescens M114 by pseudobactin M114: the pbrA sigma factor gene does not mediate the siderophore regulatory response. FEMS Microbiology Letters 144 p61-66
  • Dowling DN, Sexton R, Fenton A, Delany I, Fedi S, McHugh B, Callanan M, Moenne-Loccoz Y, O’Gara F. (1996) Iron regulation in plant-associated Pseudomonas fluorescens M114: implications for biological control. Molecular Biology of Pseudomonads p502-511
  • Brazil GM, Kenefick L, Callanan M, Haro A, De Lorenzo V, Dowling DN, O'Gara F. (1995) Construction of a rhizosphere pseudomonad with potential to degrade polychlorinated biphenyls and detection of bph gene expression in the rhizosphere.  Applied and Environmental Microbiology 61 p1946-1952
  • Sexton R, Gill Jr P, Callanan M, O'Sullivan D, Dowling DN, O'Gara F. (1995) Iron‐responsive gene expression in Pseudomonas fluorescens M114, cloning and characterization of a transcription‐activating factor, PbrA. Molecular microbiology 15 p297-306


  • Callanan M, Sakwinska O, Bourdin G, Duboux S, Ananta E. (2017) Lactobacillus plantarum CNCM I-4026 preparations and skin health
  • Callanan M, Schmitt C, Michel M, Pas M, Donato-Capel L. (2017) Whey protein aggregates
  • Callanan M, Ananta E, Duboux S, Bruttin A, Jankovic I, Sakwinska O, Bourdin G. (2016) Lactobacillus plantarum NCC2936 preparations and oral health