Plasticizer effect on grease barrier and color properties of whey-protein coatings on paperboard

Whey protein concentrates with similar to80% protein (WPC-80) plasticized with 0.64 M glycerol or sucrose, or with 0.34 or 0.64 M sorbitol or polyethylene glycol (PEG) 200, produced flexible films. WPC-80 with hydrolyzed lactose required addition of less sucrose to produce flexible films. WPC-80 films formed as coatings on paperboard gave a grease barrier comparable to WPI film-coatings. Long-term ambient storage of WPC-80 coated paperboard indicated that the use of sucrose as plasticizer imparted good grease resistance and minimized plasticizer migration.