Cow milk contains a blend of A1 and A2 beta-casein proteins. Dairy industry marketers have recently seized on A2.

Cow milk contains a blend of A1 and A2 beta-casein proteins. Dairy industry marketers have recently seized on A2. Photo: Bloomberg

EXCLUSIVE 

Science is the new battleground in the milk wars and a2 Milk is strengthening its arsenal.

Science is the new battleground in the milk wars and A2 Milk is strengthening its arsenal.

The fast-growing New Zealand company has armed itself with the first human scientific study that reveals its controversial namesake protein can be easier to digest than regular milk.

The European Journal of Clinical Nutrition has published the research from Curtin University in Perth. A2 Milk funded the study, which showed people who consumed the A2 protein were less susceptible to bloating and other stomach aches than those who consumed the A1 protein.

Regular cows milk contains a blend of the A1 and A2 beta casein proteins. But it is A2 that marketers have seized, despite the science around the protein being until now inconclusive.

Prominent nutritionist Dr Joanna McMillan said the Curtin study was the first step in clarifying some of the milk claims in the health market. But she said more research was needed.

“This study has recorded the symptoms. The next phase of the study is to understand what is happening at gut level,” Dr McMillan said.

Bigger milk processors have been fighting back against A2 Milk, which has won more than 5 per cent of Australia's fresh milk market from its rivals since launching in 2007. It is the only company that produces milk with the only A2 protein, which many people who struggle to digest regular milk saying they can drink A2 without any issues.

Last month bigger rival Lion rebranded its Pura milk products, saying its “naturally contains A2”, with new tests revealing it accounted for 50-70 per cent of its beta protein content, with A1 comprising the remainder.

This triggered the ire of nutritionists and consumer advocate group Choice which said all that had changed was Pura’s label, not the actual milk, and was therefore confusing customers.

It comes amid a grocery price war that Coles and Woolworths ignited four years ago when they slashed the price of their private label milk to effectively $1 a litre, putting pressure on branded players.

Dr McMillan slammed the marketing of some milk companies, saying that A1 was the protein people had difficulty digesting, regardless of how much A2 was blended into the product.

“These milks that are suddenly saying contains A2 beta casein protein shows that they don’t understand the issue or they are deliberating misleading the public,” Dr McMillan said. “It has nothing to do with the A2, it’s more to do with avoiding the A1, if it’s a problem you.”

The Curtin study involved 41 men and women. After a two week “dairy wash out” in which they drank rice instead of cows’ milk, they consumed 750ml a day of either A1 or A2 milk. After two weeks they had another “was out”, then swapped milks, which they drank for another two weeks.

The blind trial showed the A1 protein milk had a 61 per cent higher bloating score and 38 per cent higher abdominal pain score compared with A2 as well as a softer stool consistency.

It has followed two animal studies that have investigated the effects of A1 versus A2. Associate professor Sebely Pal of Curtin University said those animal studies had shown that the A1 protein released a peptide called BCM-7, which has been linked to gut inflammation. She said the A2 protein didn’t release this peptide.

Associate professor Pal said although A2 funded the study, the company had no input into its design or influence in the results.

“It’s irrelevant where the funding comes from. As researchers we are very objective when we carry out these studies,” associate professor Pal said.

“It has gone through a rigorous peer reviews. International researchers have torn the data apart so when it’s published it’s of the highest quality.”

A2 Milk Australia chief executive Peter Nathan said the trials confirmed what the company’s customers had been saying about the product.

“Science will always catch up with human experience,” Mr Nathan said.