http://fourfoldhealing.com/2009/03/1...09-newsletter/Milk consists of three parts: 1) fat or cream, 2) whey, and 3) milk solids. For this story we are only concerned about the milk solid part, as the fat and whey don’t have this “devil”. The milk solid part is composed of many different proteins which have their own names, lactose, and other sugars. It is the protein part of the solid we’re interested in. One of these proteins is called casein, of which there are many different types, but the one casein we are interested is the predominant protein called beta- casein.
As you may or may not know, all proteins are long chains of amino acids that have many “branches” coming off different parts of the main chain. Beta casein is a 229 chain of amino acids with a proline at number 67 – at least the proline is there in “old- fashioned” cows. These cows with proline at number 67 are called A2 cows and are the older breeds of cows (e.g. Jerseys, Asian and African cows). Some five thousand years ago, a mutation occurred in this proline amino acid, converting it to histidine. Cows that have this mutated beta casein are called A1 cows, and include breeds like Holstein.
Butter is OK from that point of view, because it lacks the milk solids. There's a tiny amount remaining, so I guess if you were worried about it (or noticed some symptoms) you could clarify the butter or buy clarified butter (sometimes sold under the Indian name ghee/ghi):
That's arguably worth doing for cooking, at any rate, since clarified butter has a higher smoke point.
Cheese? I guess it's best to buy cheese from A2 cows. In practice that means buying cheese from producers who use traditional dairy breeds - French cheeses for example:
Or eat goat's cheese or ewe's milk cheese instead.Consider French cheese – mostly due to culinary snobbery, the French never accepted these A1 breeds of cow, claiming they have lousy milk.