Tensile and moisture barrier properties of whey protein–beeswax layered composite films

✍ Scribed by Sea C Min; Theeranun Janjarasskul; John M Krochta

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 151 KB
• Volume: 89
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.3434

✦ Synopsis

Abstract

BACKGROUND: There is a lack of research on producing layered protein–lipid composite films with improved tensile and barrier properties compared to films from individual components. Several film‐forming parameters were hypothesized to influence the extent to which lipids were either dispersed within or layered upon whey protein films. Film‐forming parameters investigated were ratio of whey protein isolate (WPI) to beeswax (BW), homogenization method, sodium chloride (NaCl) concentration, and BW particle size.

RESULTS: Film percent elongation (E) increased, while tensile strength (TS) and elastic modulus (EM) decreased when BW was incorporated into WPI films, demonstrating a lubricant effect of the BW. Mean water vapor permeability values for WPI film decreased by 57% when the film composition was modified by the addition of 40% BW. BW phase separation was observed in all of the tested films. Particle size of BW in the film‐forming emulsions was larger in the presence of NaCl (100 mmol L^−1^), indicating a neutralization of particle charge. However, the addition of NaCl did not improve the moisture barrier of WPI‐BW film over the range of film‐forming conditions used in the study.

CONCLUSION: The results from this study are useful in determining formulations and conditions for the production of composite films from WPI and BW with improved tensile and moisture barrier properties. Copyright © 2008 Society of Chemical Industry