Whey Protein Isolate and α‐Lactalbumin Recovery from Lactic Acid Whey Using Cation‐Exchange Chromatography

ABSTRACT: The objective of this work was to develop a process to fractionate proteins from lactic acid whey, which is underused compared with sweet whey, using food‐grade buffers and cation‐exchange chromatography. Bound proteins were desorbed either all at once to make whey protein isolate (WPI), or in 2 steps to 1st make α‐lactalbumin (ALA) and then WPI depleted in ALA. Recovery and purity using lactic acid whey were comparable to previously reported processes using sweet whey. Capacity and throughput were slightly lower using lactic acid whey. This research provides a basis for adding value to the 6 million metric tons of lactic acid whey produced annually in the United States.