DSA Lab Services – an independent dairy specific laboratory

The Dairy Standard Agency (DSA), as a non-profit organisation, has established an independent dairy specific laboratory, namely DSA Lab Services. The laboratory is situated at the DSA head office in Centurion and its primary function is the production and import of reference standards that apply to the analysis of raw milk parameters for fat, protein, lactose, freezing point, milk urea nitrogen (MUN), somatic cell count (SCC), as well as skimmed milk (fat and protein), goat milk (fat and protein), and cream (fat and protein). The laboratory is also geared to conduct microbiological testing and is maintaining standard operating procedures aligned with the ISO/SANS 17025.

The project purpose is to:

• Establish and maintain an industry-independent national laboratory service for the supply of standardised imported and national reference standards to the dairy industry, private, and other laboratories for the calibration of high-frequency measuring equipment used in the determination of fat, protein, lactose, MUN, and SCC.
• To provide a simplified ring test, with the inclusion of a test report, which will contain statistical calculations, evaluations, and maximum allowable deviations.
• To conduct analytical functions that include microbiological and compositional testing of samples, as well as metrological compliance determination of dairy samples (where applicable).
• To perform the laboratory test required for investigations regarding complaints of non-compliance.
• To assist with the technical execution of special investigation projects where applicable to tests performed by the laboratory.

The project is a result of the lack of national standardised standards with appropriate metrological values for the calibration of laboratory instruments during the determination of fat, lactose, protein, MUN, and SCC of milk, which subsequently create technical barriers and add to legal disputes that is not in the interest of the South African organised dairy industry.

Reference standards are to be imported from Qlip, Netherlands. Imported standards are to be used for the determination of all the parameters, fat, protein, lactose, MUN, and SCC. This will also include parameters such as Total solids and Freezing point depression.

In conjunction with the above services, the supply of standards for other dairy products, as well as screen tests (product composition, microbiological testing, and metrological measurement) as part of the DSA national monitoring programme relating to milk and other dairy products, and cost-effective services in the interest of the dairy industry are also to be rendered.

The following services can be rendered by the laboratory:

• Phosphatase in milk
• Inhibitory substances in milk
• Freezing point depression (FPD)
• Fat, protein, lactose, solids non-fat, total solids
• E.coli and coliforms in milk and dairy products
• Aerobic counts in milk and dairy products
• Bacillus cereus in milk and dairy products
• Staphylococcus aureus in milk and dairy products
• Enterobacteriaceae in milk and milk products
• Lactic acid bacteria in cultured products
• Yeast and moulds in dairy products
• Presence of Listeria spp. in milk and dairy products
• pH measurement in milk and dairy products
• Compositional testing of cheese, cultured products, butter, and whey powder

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