Being one of the best sources of various proteins and calcium, milk is considered very good for health. The composition of milk consists of two major protein classes – casein and whey. Among those proteins is the casein, which makes about 80 per cent of the total content of protein. Then there are two types of these β-casein proteins – A1 and A2, which are about 30 per cent of the casein content. So basically, a quarter of proteins you consume while drinking milk are β-casein.
The A2 milk contains only β-casein A2 protein and rest composition is relatively similar to the regular milk like potassium, calcium, vitamin D and other proteins. Desi Indian cows are the ones which produce the A2 protein milk along with amino acid called Proline. In the hybrid breeds, this proline gets converted to histidine due to genetic modifications. These are the breeds of cows which produces A1 milk.
The β-casein A1 and A2 are functionally similar but they differ in the way they are digested. Digestive enzymes break the β-casein A1 when it reaches the small intestine. This process results in the release of β-casomorphin 7 (BCM-7), which is a seven-amino acid peptide chain. Different people react differently to this BCM-7. This results in different responses among different people and sometimes this leads to lactose intolerance. What makes β-casein A2 proteins better is that this peptide chain is not released during the digestion of A2 milk. Some people who are known to have issues in digesting the regular A1 dairy or hybrid milk found that A2 milk doesn’t cause issues and is good for consumption.