From 5% w/v whey protein isolate (WPI), whey protein/lipid emulsion edible films were produced that were sorbitol- or glycerol-plasticized, containing butterfat (0.2% w/v) or candelilla wax (0.8% w/v). Thermal properties of the films determined by Differential Scanning Calorimetry (DSC) showed onset temperatures (To) of 126 to 127°C for sorbitol- and 108 to 122°C for glycerol-plasticized films. To values were used as the basis for heat sealing temperatures. Temperature (110, 120, 130°C), pressure (296, 445 kPa), and dwell time (1, 3 s) affected seal strength. Optimum heat sealing temperature was 130°C for sorbitol- and 110°C for glycerol-plasticized films. All films were heat sealable with an impulse heat-sealer. Electron Spectroscopy for Chemical Analysis (ESCA) of the surfaces of both sealed and unsealed films showed increase in hydrogen and covalent bonds involving C-O-H and N-C, which may be the main forces responsible for the sealed joint formation of the films.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Food Science|
|State||Published - 2001|
ASJC Scopus subject areas
- Food Science