FUNCTIONAL-PROPERTIES OF EDIBLE FILMS USING WHEY-PROTEIN CONCENTRATE

Methodologies were developed to form edible films of simple proteins or protein-lipid composites using whey protein concentrate. The functional properties of whey protein concentrate films were compared with those of the films derived from sodium caseinate, potassium caseinate, calcium caseinate, and whey protein isolate. Water vapor permeability of simple whey protein concentrate film was lower than that for films of sodium caseinate, potassium caseinate, and whey protein isolate. Composite whey protein concentrate film had the lowest water vapor permeability of all the milk protein films. The ultimate tensile strengths of simple whey protein concentrate films were similar to those of caseinate films. Whey protein concentrate films exhibited lower puncture strengths than did films from other milk proteins except simple film from sodium caseinate. Whey protein concentrate and isolate films had higher elongation values than did simple calcium caseinate films. Transmission electron microscopy revealed the presence of residual milk fat embedded in the protein matrix in whey protein concentrate films. Whey protein concentrate films had good water vapor barrier and mechanical properties that were comparable with those of films from other commercial milk proteins.