Raw Milk Testing

The dairy testing labs at the Agriculture & Food Laboratory (AFL) offers accredited testing for milk producers and manufacturers of dairy products. All of our clients benefit from our excellent industry reputation for providing accurate and timely analytical results for over 40 years.

Our raw milk quality testing encompasses farm bulk-tank-milk and individual bovine, goat, sheep samples. Raw milk tests range from composition, somatic cell count, total bacteria count, antibiotic residues to added water testing. Note, these tests are only suitable for unprocessed raw whole milk.

Our raw milk quality testing includes:

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Our testing is carried out in a state-of-the art facility with a mature and robust quality system.  Please refer to our current Scope of Accreditation for more information.


Antibiotic Residues

We work closely with provincial legislators and producer associations in the milk sector.  We provide qualitative rapid and cost effective testing for the major classes of antimicrobials and other drug classes in raw milk.  The following drug groups are available for testing:

  • Amphenicols
  • Aminoglycosides
  • Beta-lactams
  • Macrolides
  • Quinolones
  • Sulfonamides
  • Tetracyclines

Composition Testing

Performed by Infrared Spectroscopy, delivering fat, protein, lactose and other solids.

Foreign Contaminant Identification

One specialty at The University of Guelph, Agriculture & Food Laboratory includes identification of a wide variety of food and production contaminants to quickly resolve customer complaints, quality defects, and potential litigation. In addition, we can produce high-magnification images of your products to assist in problem solving and product development. For third party investigation, we offer unbiased scientific expertise and aid in identifying the time and source of the contamination. Our team can even help assure you that some concerns are due to natural causes, thereby avoiding costly product recalls. Whether your concern is for safety of raw ingredients, or finished goods, contact us, we are here to help.

We can save you time and money by quickly identifying contaminants found in processing material or during production, enabling you to solve the problem and get back to production. As part of The University of Guelph, we have access to experts on campus to help identify difficult specimens. We can compare a known compound to an unknown one, to help trace the source of contamination. In many cases the testing is non-destructive and extremely small samples can be analyzed. We can also offer same-day emergency testing.

Common contaminants identified in our lab include:

Metal Fragments Elemental identification (e.g. iron, lead) identified by scanning electron microscopy and x-ray microanalysis.
Polymers/Plastics All different types such as polypropylene, nylon, PET, etc.
Glass Elemental composition and refractive index is specific to various types of glass, e.g. lead crystal, window glass, etc.
Plant/Animal Tissue Plant and animal pathologists are available to assist with identification.
Blood Determination of human versus non-human.
Food Ingredients Crystal aggregates, precipitates, etc.
Fungi Morphological identification can be provided; samples may be forwarded for culture when appropriate.
Rodent Contamination Hair, feces, etc.
Many more... Organic contaminants, crystalline materials, insect identification  etc.

Please contact us to inquire about other foreign material identification services.

Freezing Point Estimate/Added Water Testing

Samples submitted for added water testing are analyzed using cryoscopy to determine the freezing point of the milk.

Somatic Cell Count

This is a count of white blood cells present in milk that indicates udder health and milk quality performed by flow cytometry.

Total Bacteria Count

Performed by flow cytometry on the FOSS Bactoscan, delivering a bacteria count.