Work area - Microbiology

Teaching & research

Various laboratory practicals are offered for students of the Bachelor's degree courses in Technology of Renewable Resources, Food Packaging Technology, Dairy Food Technology and for students of the Master's degree course Dairy and Packaging Industry.

Microbiological basics
The first techniques of microbiological laboratory work are learned here. Knowledge of diagnostic criteria on a morphological, metabolic-physiological and genetic basis is practically tested.

Microbiology
Relevant microorganisms are diagnosed, differentiated and cultivated taking into account their epidemiological and technological significance. This includes the handling and detection of spoilage germs, beneficial microorganisms and microorganisms relevant to the dairy industry.

Microbiological analytics
This is about detailed microbiological analytics of saprophytic and technologically useful microorganisms based on classical microbiological methods and molecular biological techniques. Preparation of HACCP concepts and action plans. Interrelationships between product quality, packaging management and milk processing are recognised and dealt with independently by selecting and applying specific microbiological analysis techniques.

Focus points of work and research

Diagnostics and epidemiology of dairy-relevant microorganisms and mastitis pathogens.
Quantitative microbiology of milk and dairy products
Microbiological control of surfaces
Determination of minimum inhibitory concentrations
Resistance test - agar diffusion test, determination of minimum inhibitory concentration
Methods of risk analysis
Interaction of the bovine teat and mechanical milk removal
Systematic care of dairy herds to improve animal health and remediation of mastitis problem farms
Therapy of sub-clinical and clinical mastitis
Pathogen multiplication in different bedding materials under different climatic conditions
Clarification of the relationship between mastitis and raw milk quality
Strain comparisons of different microorganisms
Classification and identification is based on proteomic fingerprinting using high-throughput MALDI-TOF mass spectrometry.
Relevance of different key germs depending on the husbandry system (pasture-stable)
Studies on the development of resistance and the reduction of antibiotic consumption in dairy production.

Interesting techniques

MALDI Biotyper Microflex LT/SH Smart

MALDI biotyper systems provide rapid, highly reliable identification and taxonomic classification of bacteria, yeasts and fungi. Classification and identification is based on proteomic fingerprinting using high-throughput MALDI-TOF mass spectrometry.

Fluorescence microscopy

A fluorescence microscope is an optical microscope that uses fluorescence and phosphorescence instead of or in addition to scattering, reflection and attenuation or absorption to investigate the properties of organic or inorganic substances. Targeted staining, in part with fluorescent dyes bound to antibodies, allows individual cell structures or specific cell types to be specifically visualised.

Flow cytometry

Two devices are available for flow cytometry. The Somascope Smart (Delta Instruments, AR Drachten, The Netherlands) is used for fluorescence optical counting of somatic cells (immune cells) in milk. The CyFlow® Space (Sysmex Europe GmbH (formerly Partec), Norderstedt, Germany) is a high-end multilaser flow cytometer and is available for scientific questions. The particles to be detected (immune cells, yeasts, bacteria) can be identified and quantified by adjusting the settings (up to 5 different light sources, 16 analysis parameters) by means of their size, granularity and staining with fluorescent dyes (volumetric absolute cell counting). The sorter module can be used to isolate specific particles, which are then available for further analysis or use.

Equipment

Classical microbiology - cultural cultivation with morphological, biochemical and serological methods (sterile benches, incubators/rooms, refrigerators/rooms, shaking incubator, water baths).
Molecular biological diagnostics - detection of relevant microorganisms for technological processing of milk and mastitis - e.g. DNA preparation, real-time PCR, RAPD, PFGE (Mx3005P qPCR System thermocycler, Agilent (former Stratagene), California, USA; InGenius gel documentation system, Syngene, Cambridge, UK)
Traacs (Bran & Luebbe) for enzymatic analysis in blood and milk
Flow cytometry - counting of somatic cells in milk (Somascope Smart, Delta Instruments, The Netherlands), cell differentiation using CyFlow® Space (Sysmex Europe GmbH (former Partec), Norderstedt, Germany)
Fluorescence microscopy (Axio Lab.A1 for cytology and immunofluorescence, Jena, Zeiss)
High-throughput MALDI-TOF mass spectrometry (MALDI Biotyper Microflex LT/SH Smart, Bruker Corporation, Billerica, Massachusetts, USA) with MBT Compass Library (Bruker Corporation, Billerica, Massachusetts, USA)