The quality of milk is changed by on-farm milk handling in ways that reduce the foaming for lattes, researchers at the University of Guelph have found.
Dr. David Kelton and one of his master’s-degree students, Hannah Woodhouse, found that narrower pipelines and pre-cooling systems change free fatty acids.
Milk that doesn’t froth has free fatty acids displacing the protein on the bubbles that should be forming and the milk either won't froth or the froth breaks down quickly, Kelton explained.
"There's a lot more turbulence in a narrower pipeline so the fat globules actually bump into each other, bump into the side of the stainless steel pipe, break apart and release those fatty acids," he said.
He said when it came to cooling milk, farmers normally do it in the bulk tank, but some pre-cooled their milk using specialized equipment.
"The farms that were cooling their milk more rapidly actually had lower free fatty acid levels," he said, but he’s not sure why.
He says they plan now to expand the pilot project to 200 farms over the next few months to learn more about how farming practices impact free fatty acids in milk. That includes looking more closely at the way milk is cooled as well as what lactating cows are being fed.
The original work involved 50 farms with higher fatty acid levels.
