DNA Testing of Milk at Haribol

At Haribol, our milk is tested for pure A2 compliance every day! Samples from each batch of milk pass through the following stages before approved for distribution and processing

Step 1


DNA is located within the nucleus of cells throughout the sample of milk and the extraction step is responsible for breaking open the nucleus and releasing the DNA molecules. This step is important for removing any debris that may interfere with the extraction. Extraction may be performed organically or through a robotic system.

Step 2


This is the process by which the quality and quantity of DNA present in a sample is measured and assessed. Determining the amount of DNA in a sample is important for success in amplification since most systems require a narrow range of input DNA.

Step 3


DNA amplification is performed through a technique known as Polymerase Chain Reaction (PCR), a process in which millions of copies of a specific sequence of DNA can be made in a few hours. This molecular “xeroxing” process is completed by precise heating and cooling of the samples in a thermal cycling pattern for multiple cycles.

Step 4

Capillary Electrophoresis (CE)

After the PCR reaction is completed it results in a large mixture of amplified DNA molecules which need to be separated in order to distinguish the various molecules from one another. This is accomplished through a process known as capillary electrophoresis. The data from this process is then collected on a computer attached to the CE instrument and through the use of a software program, a DNA profile is developed to ascertain whether the milk is A1 or A2.

Step 5

Rejection Of A1 Milk

Any sample batch found to contain A1 beta-casein is rejected and only samples with A2 beta-casein are dispatched for further packing.


All about A2 Milk