Consumers can't seem to get enough of protein. But a looming shortage means companies may not be able to get enough, either.

Once considered a cheap byproduct of the cheese manufacturing process, whey protein concentrate is one of the most in-demand ingredients as food and beverage manufacturers look to capitalize on surging demand for protein-fortified products. The unprecedented demand is creating shortages, with some suppliers sold out for the remainder of the year, according to the USDA.

Unsurprisingly, the dearth of supply is leading to higher prices. Standard whey powder prices have increased by more than 50% since January, according to DCA Market Intelligence.

Prices are higher for powders with higher concentrations of protein. For whey protein concentrate with 80% protein content, spot prices were topping $11. Protein isolate, which is more than 90% protein by weight, remains "firmly in the $12s," according to USDA.

BellRing Brands, owner of Premier Protein and Dymatize protein shakes, is seeing whey protein prices reach "historic highs," CEO Darcy Davenport said on an earnings call this week. Tight supply is also affecting prices of non-fat dry milk, another ingredient used in protein fortification and a key ingredient in BellRing's protein shakes.