A2 testing: an alternative to genetic approaches with raw milk testing
If you work in the dairy industry, you’ve probably heard of A2 β-casein milk. If you have a dairy farm, you may have already started, or considered starting A2 testing. The demand for A2 β-casein milk is growing as consumers interested in their overall health become aware of the potential side effects and human health risks of the A1 variant of β-casein.
Understanding the science is the behind A2 β-casein milk is the first step to evaluating the different testing options.
Briefly, milk has lots of different proteins, but casein is the most abundant (almost 80% of the protein content). There are 12 variants of casein, and the A1 and A2 β-casein variants are the most common. A1 and A2 β-casein only have a single nucleotide difference in their genetic code, resulting in an altered amino acid base, leading to large structural differences in the final protein.
This is important, because when the A1 β-casein protein is digested it results in 4-times higher levels of β-casomorphin 7 (BCM7) than digestion of the A2 protein. Studies show that BCM7 is a potential health hazard with implications in many diseases and negative long-term consequences. We are not supporting or investigating these claims, so independent research is suggested.
No matter the research, consumers are starting to desire pure A2 β-casein milk to protect their health. The only way to have A2 β-casein milk is to have A2 cows. Cows have the potential to have only the A1 variant, only the A2 variant, or a combination of both.
Since the difference between the two is a nucleotide in the proteins’ genetic code, labs can look at bovine DNA to determine which variant is present. While effective, this means every cow must be tested, because if any A1 β-casein is present in a batch of raw milk, then the whole batch must be labeled as A1/A2. Thus, genetic testing, which typically requires a tissue or blood sample each cow, is extremely time consuming, especially considering the increased sample preparation, experimental, and data processing time involved for accurate results.
If marketing A2 β-casein milk, it is critical that the products do not contain any A1 β-casein, and this starts at the level of raw milk supplier. If a brand or retailer is suspected of fraudulent A2 claims, the ultimate blame can work back to the ingredient supplier, resulting in a costly investigation that can harm company revenue and reputation.
Luckily, Eurofins has a solution for batch testing!
With the first A2 β-casein test that directly measures raw milk and dairy products, Eurofins DQCI is combining innovation with a passion for dairy safety. We use a simple ELISA assay to check if any A1 proteins are present in raw milk from individual cows, or an LC-MS/MS method for a more detailed look at protein levels in raw milk and finished products.
Our labs offer a variety of testing options to fit your needs.
ELISA-based assays:
ELISA is an assay that uses antibodies to capture and detect specific proteins. Using this approach, we can determine if any A1 proteins are present in an individual cow’s milk. If milk is labeled as A2, any trace of A1 means it is not A2. So, we can use this assay to confirm raw ingredient claims and analyze herd structure. If A1 is detected in the sample, we can conduct more specific tests to measure the A1 and A2 β-casein levels using LC-MS/MS.
LC-MS/MS:
The LC-MS/MS method provides information about protein quantity. A1 and A2 protein levels can be reported as µl/mL or µg/g and as a proportion of total protein content. LC-MS/MS can be used for individual cows, batch samples, and more complex matrices, like finished products. Measuring A1 and A2 β-casein levels provides insight into the origin of the A1 proteins, helping determine if the source was an A1 cow or a matter of equipment contamination. This LC-MS/MS method is only offered by the Eurofins network.
The unique combination of testing options, including ELISA testing for individual cow milk and LC-MS/MS for protein quantification and finished product evaluation, makes Eurofins DQCI the ideal 3rd party testing lab for A2 β-casein milk.
Contact us today to learn more about our A2 testing offerings! Learn more here.
