News media throughout Australia reported this week that a cheese byproduct known as permeate was being added to fresh milk by fluid milk processors in that country.

According to this article, permeate is a “watery, greenish waste product from the production of cheese” that forms up to 16 percent of the fresh milk in Australia. Other reports said Australian milk companies had been “exposed.”  

These types of reports are taken very seriously following the “pink slime” episode in the U.S. meat industry. In fact, one blogger here in the U.S. wrote that the Australian story has all of the elements of pink slime: a food additive that appears safe, but has a “yuck” factor. His headline referred to “green slime.”

Few, if any, of the news articles differentiated between whey permeate ― the kind that comes from cheese-making ― and milk permeate. Milk permeate is the result of an ultra-filtration process that allows processors to extract sugars and proteins in order to standardize protein levels.  

The news media did not explain the difference, and this created a certain amount of confusion, according to Glenys Zucco, dietitian with Dairy Australia.

“We know there was a lot of noise on Twitter, a lot of noise online…. A lot of people called in concerned about what’s in their milk,” Zucco told Dairy Herd Management in a telephone interview.

Zucco and her colleagues explained that the milk permeate being used is nutritious and healthy, and the processors aren’t adding anything that wasn’t in the milk already.

While processors in Australia are allowed to add milk permeate, it is illegal for them to add whey permeate or cheese byproduct.

In the United States, neither milk permeate from filtered milk nor whey permeate is permitted to be added to fluid milk under the U.S. Federal Standard of Identity.

Other countries may permit standardization with other milk ingredients, such as permeate or lactose, but not the United States, according to a statement from the International Dairy Foods Association.