A team of researchers at the University of Guelph are studying why Canadian baristas sometimes have problems foaming milk for their customers’ lattes, and it starts with on-farm milk handling.
Dr. David Kelton, Dairy Farmers of Ontario Dairy Cattle Health Research Chair, graduate student Hannah Woodhouse, and animal bioscience undergraduate student Mikayla Ringelberg are studying ways to reduce free fatty acid (FFA) levels in milk, which hinder frothing.
So far, they have found measures that can be taken on the farm to ensure foamy milk.
High FFA levels can be cause by damage to the milk fat globule membrane, which often occurs during handling after milking. Damage to this membrane releases FFAs.
“There’s a genetic component to elevated FFA levels in dairy cows, but we are finding many contributing farm-level factors, some of which can be managed to optimize the quality of milk,” says Kelton in a press release. “These include aspects of lactating cow nutrition, but more so, how the milk is handled after it leaves the cow.”
The research team found that narrow pipelines and lack of pre-cooling before milk enters a bulk tank can lead to elevated FFA levels. Narrower pipelines increase turbulence, which physically disrupts the fat globules in milk, and pre-cooling decreases bacteria counts in milk, which would otherwise be available to release lipases (enzymes that break down fat).
Kelton says that further work needs to be completed to confirm the team’s research results and identify other possible factors in elevated FFAs.
“Milk is a superb nutrient-dense product, but it’s also a highly fragile commodity,” says Kelton. “To optimize the product quality that ends up on store shelves, it’s crucial to improve handling methods. Our research has made us think more critically about how milk is handled after it leaves the cow.”