Laboratory methods for microbiological assessment of milk

Microbiological assessment is the cornerstone for understanding the safety of food that is produced, marketed and consumed. The Safe Food, Fair Food project aims at adapting and implementing risk assessment in informal markets in four countries in sub-Saharan Africa: Ethiopia, Senegal, Tanzania and Uganda. The outcomes of the project will help identify suitable risk management activities to be piloted in selected livestock value chains, including dairy in Tanzania.
In this context, the project is assessing the microbiological hazards in the milk in dairy farming households in two regions in Tanzania: Morogoro and Tanga. The microbiological quality of the milk stored and consumed at the farmers’ households will be assessed through hygienic indicators (enumeration of mesophilic bacteria, Enterobacteriaceae and coagulase-positive staphylococci) and identification of the main foodborne pathogens (Salmonella spp. and Listeria monocytogenes). Milk collected from the cows in the farmers’ herds will be tested for the presence of mastitis-causing microorganisms including Streptococcus agalactiae and Staphylococcus spp.
On 17-23 March 2014, BfR and ILRI held a training workshop for five MSc students and two laboratory technicians from SUA towards developing and strengthening individual and institutional capacity in microbiological assessment of food. Lectures and practical sessions were combined throughout the course to provide theoretical basis and practical experience in enumerating, isolating and identifying various microorganisms, including milk-borne pathogens.
The specific learning objectives were:
To gain knowledge on basic concepts of public health, risk assessment, microbiology and laboratory work.
To understand the principles and different techniques of microbiological analysis of food (milk).
To be able to perform a range of laboratory methods on milk hygiene and to enumerate, isolate and identify various foodborne and mastitis causing pathogens.