Originally all cows’ milk only contained the A2 protein type and no A1 protein type. That’s why we say a2 Milk™ is the original milk.
Originally all cows produced milk containing only the A2 type of beta casein protein
Following domestication the A1 protein type emerged through the genetic mutation (approximately 70% of the cows today produce milk containing the A1 protein type)
Today, most ordinary cows’ milk contains a mix of A1 and A2 protein types
All our milk products naturally contain the A2 protein and are completely free from the A1 protein type