Whey protein isolate coating material for high oxygen barrier properties: A scale-up study from laboratory to industrial scale and its application to food packaging

Abstract

To apply whey protein isolate (WPI) as a food packaging material industrially, a three-step study was performed. First, the WPI coating solution was screened for plasticizer type, plasticizer concentration, and pH to minimize its oxygen permeability. The production batch size was scaled-up from 1 to 320 L. Next, the PET film was sequentially coated with the WPI and laminated with a linear low-density polyethylene (LLDPE) film using an industrial manufacturing facility. The developed multilayer (PET/WPI/LLDPE) film was compared to the aluminum oxide (AlOx)-deposited multilayer (PET/AlOx/LLDPE) film. The PET/WPI/LLDPE films showed high oxygen and water vapor barrier properties. Finally, the PET/WPI/LLDPE films were applied as frozen shrimp fried rice (SFR) packaging. For 6 months, they delayed peroxide formation in the SFR samples, as much as the PET/AlOx/LLDPE films did. These results indicated that the developed film has high potential as a packaging material for frozen foods in practical applications.