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What is A2 milk?
Milk protein is made up of 80% casein proteins and 20% whey proteins. There are 4 differend kinds of caseins, one of which is β-casein (Beta Casein).
Beta casein comes in two different structure types, A1 and A2. The difference between A1 beta casein and A2 beta casein is the amino acid at position 67 of the beta casein molecule.
The difference in structure between the beta casein variants can lead to a difference in their breakdown during digestion.