Water Vapor Permeability of Whey Protein Emulsion Films as Affected by pH
Article first published online: 20 JUL 2006
Journal of Food Science
Volume 64, Issue 4, pages 695–698, July 1999
How to Cite
Pérez-Gago, M.B. and Krochta, J.M. (1999), Water Vapor Permeability of Whey Protein Emulsion Films as Affected by pH. Journal of Food Science, 64: 695–698. doi: 10.1111/j.1365-2621.1999.tb15112.x
- Issue published online: 20 JUL 2006
- Article first published online: 20 JUL 2006
- Ms received 10/29/98; revised 2/12/99; accepted 3/18/99.
- whey protein;
- edible films;
- emulsion stability;
- water vapor permeability
The water vapor permeability (WVP) of whey protein isolate-beeswax emulsion films was investigated as related to pH. Lower WVP was observed for films cast from solutions at pH 7.0. When pH of the film-forming solution was lowered, resulting film WVP increased. At the isoelectric point, WVP was the highest. As pH of the emulsion approached pI, a sharp change in viscosity occurred due to an increase in protein aggregation. This increase in viscosity probably lowered lipid mobility and reduced interconnectivity among lipid droplets, resulting in the higher WVP. For minimum WVP, such films should be applied at pH different from pI.