Whey’s Transformation From Lowly Byproduct to Hot Commodity

Whey, long treated as a waste stream from cheese production, has become one of the dairy industry’s most valuable ingredients as demand for protein-fortified foods and beverages continues to surge, driven at least in part by the advent of glucagon-like peptide (GLP-1) weight loss drugs. Experts say the key to successfully formulating with whey lies in understanding how different whey ingredients function in a product and how to optimize those properties for specific applications.

High-quality proteins help preserve muscle during dieting, explains Kimberlee Burrington, vice president of technical development at the American Dairy Products Institute. People using GLP-1 drugs often prefer smaller servings because they tend to feel full quickly, but they need to maintain adequate protein intake.

“I think it’s super challenging for product developers because they’re being told to make new products and to put a lot more protein into those products than they normally would have,” Burrington says.

Using whey as a high-protein ingredient isn’t new, Burrington continues. She pinpoints the mid-1980s as the period when whey research began in earnest, adding that whey’s nutritional value is well documented. Of the milk that’s used in cheese making, only about 10% becomes cheese; the remaining 90% is whey, which retains half of milk’s nutritional value.

Different whey concentration processes create whey powders with varying protein levels. Powders with less than 90% protein are classified as whey protein concentrate, while those containing 90% or more are whey protein isolates.

There’s more than one type of whey, and selecting the right one is important for optimal product formulation.

There’s more than one type of whey, and selecting the right one is important for optimal product formulation. Producing sweet cheeses like cheddar and mozzarella generates sweet whey, which has a pH of about 6.4. Acidic products like Greek yogurt and sour cream produce acid whey, which has a pH of about 4.3.

U.S. cheese production skews toward sweet varieties, so there’s a greater supply of sweet whey available, says Baheeja Zaitoun, a research fellow at the Dairy Products Technology Center at California Polytechnic State University San Luis Obispo.

“For sweet whey, they end up drying it and getting those powders,” she says. “They can be used in infant formulas and other applications like high-protein bars or cookies or drinks.”

Formulation Considerations

Sweet whey is easier to formulate with than acid whey for several reasons, including the fact that acid whey is trickier to dry and more difficult to handle. “That limits its applications,” says Burrington.

Additionally, acid whey’s lower pH gives it an acidic flavor that usually needs to be masked. Even sweet whey can contribute astringent notes, however, Zaitoun says.

Whey-based high-protein drinks are often cloudy in appearance because of their pH, which can reduce their appeal to consumers, who tend to view clear protein beverages as more refreshing and thirst-quenching.

Zaitoun also points out that when whey is used in products like cookies and protein bars, those products can harden quickly, requiring formulators to compensate if they want to maintain softer texture.

Then there’s price, which has reached an unprecedented high as demand has risen. Whey protein isolate currently sells for about $14 a pound and whey protein concentrate for around $12 a pound, “which has never ever happened in the history of whey protein,” says Burrington.

Now, however, there’s another option that researchers are excited about—whey protein phospholipid concentrate, a coproduct of whey protein isolate production. It contains about 70% protein and 15% fat and is much less expensive than whey protein isolate. Early studies have shown that it may provide bioactive compounds that support gut and brain health.

“This is the newest thing, and everybody now is trying to find a way to best use it,” says Zaitoun.