Researchers say the high salt content of whey—the watery part of milk left behind after cheesemaking—helps make it one of the most polluting byproducts in the food processing industry. In a new study, chemists demonstrate the first electrochemical redox desalination process used in the food industry, removing and recycling up to 99% of excess salt from whey while simultaneously refining more than 98% of whey's valuable protein content.