New Zealand scientists find technique to foil dairy product imitators

New Zealand scientists said Tuesday they were developing a method to prove infant formula and other dairy foods labeled as New Zealand produce were the genuine article, in a move to fight counterfeit products in overseas markets. Scientists at the University of Otago and the government's Institute of Geological and Nuclear Sciences (GNS Science) said they had completed preliminary work to identify the geographical origins of milk powder. The scientists identified a distinctive natural isotope -- or hydrogen atom-- signature in New Zealand's rainfall that passed through pasture and into milk products. Troy Baisden of GNS Science said scientists had made progress in measuring hydrogen isotopes in rainfall and biological materials, such as milk, by having the ability to look at the hydrogen isotopes in rainfall from each storm during the milk production season. "We work with monthly rainfall samples from all over New Zealand. We turn information derived from these samples into a map of daily rainfall chemistry using climate data from NIWA (the government's National Institute of Water and Atmospheric Research), " Baisden said in a statement. Otago University then used mass spectrometry to measure the ratio of the two hydrogen isotopes of bulk milk powder, or individual fatty acid compounds. New Zealand exported about 2 billion NZ dollars (1.63 billion U. S. dollars) worth of milk products to China each year, but there had been a recent rise in imitation, and sometimes dangerous, dairy products, said the statement. Otago University Associate Professor Russell Frew said the technique opened the possibility of verifying the origin of the milk component of mixtures such as infant formula, as well as products like butter and cheese. "The major advance here is that we are able to link the milk data to the rainfall map and hence use this to identify the origin of the commodity," Frew said in the statement. Baisden said the proof-of-concept work was very promising and was being developed further.