Development of edible films obtained from sub-micron emulsions based on Whey Protein Concentrate, Oil/Beeswax and Brea Gum

J.P. CECCHINI; M.J. SPOTTI; A. PIAGENTINI; V.G. MILT; C. CARRARA

FOOD SCIENCE AND TECHNOLOGY INTERNATIONAL

SAGE PUBLICATIONS LTD

Lugar: London; Año: 2017

1082-0132

Edible films with whey protein concentrate (WPC) with a lipid component, sunflower oil(O) or beeswax (W), to enhance barrier to water vapor were obtained. Brea gum was usedas emulsifier, and also as matrix component. In order to achieve emulsion with small andhomogeneous droplet size, an ultrasonicator equipment was used after obtaining a pre%emulsion using a blender. The films were made by casting. Effects of lipid fraction ondroplet size, zeta potential, mechanical properties, water vapor permeability (WVP),solubility and optical properties were determined.The droplet size of emulsions with BG decreased when decreasing the lipid content in theformulation. The zeta potential was negative for all the formulations, since the pH wasclose to 6 for all of them and pI of BG is close to 2.5, and pI of ß%lactoglobulin and %lactalbumin (main proteins in WPC) are 5,2 and 4,1 respectively. Increasing W or SOcontent in blended films reduced the tensile strength and puncture resistance significantly.BG and WPC films without lipid presented better mechanical properties.The presence of lipids decreased the WVP, as expected, and those films having BGimproved this property. BG films were slightly amber as a result of the natural color of thegum. BG has shown to be a good polysaccharide for emulsifying the lipid fraction andimproving the homogeneity and mechanical properties of the films with WPC and beeswaxor oil.