Composite films prepared by casting wheat starch and whey-protein isolate at proportions of 100–0%, 75–25%, 50–50%, 25–75% and 0–100% were characterised. Combination of both substances gave continuous and homogeneous films. The more the starch is in a film, the more dull is the appearance. The highest water adsorption was observed for pure whey-protein films and the lowest for pure wheat starch films with the final water content of 0.264 and 0.324 g water g d.m.−1, respectively. An exponential equation well fitted the experimental data of water vapour kinetics (R2≥ 0.99). The highest values of thickness and elongation at break were observed for films obtained by blending of wheat starch and whey protein. With the increasing content of whey-protein isolate, the values of the swelling index and tensile strength increased from 34.31% to 71.01% and from 2.29 to 8.90 MPa, respectively. The values of water vapour permeability depended on humidity conditions and decreased slightly with the increasing content of whey-protein isolate.
No takes yet. Share an insight, caveat, or question.
Basiak et al. (2014) studied this question.