United States raw milk debate concluded that "raw milk poses a realistic health threat due to a possible contamination with human pathogens. It is therefore strongly recommended that milk should be heated before consumption. With the exception of an altered organoleptic [flavor] profile, heating (in particularly ultra high temperature and similar treatments) will not substantially change the nutritional value of raw milk or other benefits associated with raw milk consumption." Pasteurization opponents say that raw milk contains bacteria beneficial to the human digestive system, but pasteurization is not selective and affects all bacteria whether beneficial or infectious. These bacteria include species considered to be probiotics,
A2 milk is impossible to determine what component or components of milk might be responsible for these effects, and it is unlikely that the expensive and complex research to determine the answers to these questions will ever be conducted. Milk with predominantly A2 protein is not a milk substitute for infants with cow milk protein allergies. The a2 Milk Company claims that people who experience discomfort drinking ordinary cows' milk may experience relief when they switch to milk with predominantly A2 protein. In the 1980s, some medical researchers began to explore whether some peptides (including peptides from casein) that are created during