A2 Milk [NZX: ATM], which is facing copycat health claims about the A2 beta-casein protein variant in its largest market of Australia, has released a study suggesting the protein doesn't provoke digestive discomfort the way the more common A1 variant does.
The Curtin University study, funded by NZX-listed A2 Milk and published in the European Journal of Clinical Nutrition, is the first clinical trial of A1 and A2 milk proteins on human digestion. A2 Milk markets its products as potentially being beneficial for people who suffer intolerance to the A2 protein, including bloating and stomach pain and it has captured some 5 percent of the Australian fresh milk market.
Among the findings was that the A1 beta-casein led to a "looser" stool consistency with the effect particularly strong for women.
"The logical next step is to source furher funding for more scaled human studies to further understand the digestion differences between A1 beta-casein in milk amongst different groups of people and that will be my focus going forward," Associate Professor Sebely Pal of Curtin University said in a statement.
Researchers at the university carried out an eight-week double-blind study of 41 people, who were fed A1 or A2 milk and then tested their stool samples and recorded symptoms such as "bloating, abdominal pain, flatus and difficulty in voiding." The study found there were differences.
"These preliminary results suggest differences in gastrointestinal responses in some adult humans consuming milk containing beta-casein of either the A1 or the A2 beta-casein type, but require confirmation in a larger study of participants with perceived intolerance to ordinary A1 beta-casein-containing milk," the researchers wrote.
A2 Milk lifted branded sales in Australia by 28 percent in its first half and when it released the results in February it estimated that it had 8 percent market share of fresh milk sold through grocery stores such as Coles and Woolworths. Earlier this year year, milk processor Lion changed the labelling on its Pura and Dairy Farmers milk to include a reference to the A2 protein, while rival dairy company Parmalat has reportedly hired a consultant to help it try to discredit the health claims.
A2 Milk shares rose 3 percent to 66 cents on the NZX today and have dropped about 19 percent this year, while the NZX 50 Index gained 6.8 percent. The stock is rated a 'buy' based on the consensus of four analysts polled by Reuters.