During the summer months, one of the beneficial fats in particular (conjugated linoleic acid, or CLA9) was found to be 60% higher.
Results from the Nafferton Ecological Farming Group study were published online in the Journal of Science of Food and Agriculture.
“We have known for some time that what cows are fed has a big influence on milk quality,” said Gillian Butler, livestock project manager for the Nafferton Ecological Farming Group at Newcastle University, who led the study. “What is different about this research is it clearly shows that on organic farms, letting cows graze naturally, using forage-based diet, is the most important reason for the differences in the composition between organic and conventional milk.”
“Future research is focusing on how to improve the nutritional composition of milk during the winter, when cows are kept indoors and fed mainly on conserved forage, said Butler.”
The study, which involved Newcastle scientists working with the Danish Institute for Agricultural Science, is part of the ongoing cross-European Quality Low Input Food project into animal health and welfare, milk quality and working towards minimizing the use of antibiotics in dairy production.
The study included 25 farms across the U.K. in two contrasting areas – South Wales and the North East. The scientists looked at three different farming systems: conventional high input, organically certified, and non-organic sustainable (low-input).
This current research confirms previous studies in the U.K., which reported higher concentrations of omega 3 fatty acids in milk from organic production systems than conventional ones.