Superiority of Dairy Proteins Affirmed

United Nations-endorsed scoring system demonstrates the superiority of dairy proteins compared to plant proteins.

The dairy industry has long claimed that milk proteins are superior to plant-based alternatives like soy. Now, with the recent recommendation from the U.N. Food and Agriculture Organization (FAO) that the food industry use the Digestible Indispensable Amino Acid Score (DIAAS) rather than the Protein Digestibility Corrected Amino Acid Score (PDCAAS) to measure protein quality, dairy has official, incontrovertible proof.

USDEC supported the change and helped introduce the world to DIAAS when it organized the Protein Quality Symposium at last November’s International Dairy Federation (IDF) World Dairy Summit in South Africa.

“DIAAS clearly demonstrates the superiority of dairy proteins compared to plant proteins,” says Laurence Rycken, IDF nutrition officer.

PDCAAS, in use since 1991, has been widely criticized for a number of reasons, including that it overestimates the amount of amino acids absorbed by the body, thus providing misleading information about the relative value of a number of protein sources. If a protein is not bioavailable, if a body cannot digest and absorb it, then it provides no benefits. Some vegetable proteins are, for example, attached to fiber and the body cannot get at them.

DIAAS quantifies only the bioavailable part—only the nutrients digested from the food. In that light, dairy gains a clear and powerful competitive edge.

“The high level of essential amino acids with high digestibility, such as the high lysine bioavailability in dairy proteins, makes dairy protein a vital food ingredient for managing protein energy malnutrition and supporting growth in young children,” says Rycken.

Data in the FAO report showed WMP to have a DIAAS score three times that of wheat protein and 10-30 percent greater than the highest refined soy isolate.

The results are particularly meaningful for food aid products and high-value applications like medical nutrition. In regions where food resources are scarce or for people whose appetites are reduced due to age or illness or for those who have difficulties swallowing due to medical treatment, protein quality becomes extremely important.

“For vulnerable segments of the population, it is crucial to pack all the nutrients they need in a small volume,” says David Clark, owner of Bovina Mountain Consulting, former director of R&D for FrieslandCampina and now a USDEC consultant. “Dairy proteins are already widely used in medical nutrition. But in some cases, formulators look toward alternative proteins. Now, it is clear how those alternatives rank vs. dairy.”

Medical nutrition was a $2.5 billion market in North America alone in 2012. It is poised for steady and strong growth, as the world’s senior population booms and people seek affordable methods to address condi­tions like sarcopenia and other diseases associated with aging.

“We will all be living longer and have various treatable ailments that benefit from this type of nutrition,” says Clark.

However, before DIAAS is fully implemented, research­ers will need to develop additional supportive data, including generating more ileal amino acid digestibility values so that a database can be created to eliminate the need for repeat testing of food sources—a time-consuming and costly endeavor.

The industry should play a role in helping facilitate the research and adoption of DIAAS, learning about it and communicating the benefits, says Clark. “A 30 percent difference with soy is huge.”

(This article first appeared in the September 2013 edition of Export Profile.)

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The U.S. Dairy Export Council is primarily supported by Dairy Management Inc. through the dairy farmer checkoff that builds on collaborative industry partnerships with processors, trading companies and others to build global demand for U.S. dairy products.