Leite A2: principais aspectos

Abstract

Cow's milk is the most consumed milk in the world, mainly for its nutritional composition and its benefits to human health. The main nutrients present in milk are protein, carbohydrate, fat, minerals and vitamins. Among the proteins in milk, caseins are in the highest amount (80%). Of these 25 - 35% are beta-caseins, and the main ones found in dairy cattle, in greater quantity are the variants A1 and A2. Beta-casein A1 is linked to the release of beta-casomorphine 7 and possible complications to human health. However, beta-casein A2 is responsible for positive health aspects, as well as increased milk yield observed in some dairy breeds and alteration in milk composition. Thus, the aim of the present review was to approach the differences between the beta-caseins A1 and A2, the allelic and genotypic frequencies of the main dairy breeds, and the prospects for the A2 milk market in the current dairy production scenario, considering that in the country there are genetic resources for milk production A2.