HEAT CURING OF WHEY-PROTEIN FILMS

Heat curing of edible whey protein isolate (WPI) films was studied as a means of improving mechanical and water vapor barrier properties, Cu ring temperature and relative humidity (RH) effects on the rate of cha nge of maximum tensile stress (TS), elongation at break (E), Young's M odulus (Y-m), and water vapor permeability (WVP) were investigated. Cu re time linearly affected TS and Y-m, while influencing E and WVP expo nentially, Increased cure temperature and reduced RH accelerated TS in crease, E and Y-m decrease, and increased improvement in WVP barrier p roperties. These data support the hypothesis that heat curing may elic it additional crosslinking of protein, yielding increased TS and decre ased E and WVP; however, further work is required to confirm this hypo thesis.