Coating of light paper with whey protein to apply as a packaging for oily products

Nowadays the application of paper in packaging is more than plastic materials, due to its properties such as lightness and biodegradability. Paper has weak barrier properties such as permeability to water vapor, gases and oil. Use of synthetic polymers such as polyethylene, latex and polyvinyl alcohol for improvement of barrier properties of the paper packaging leads to environmental problems. To eliminate these problems, films and coatings based on polysaccharides, proteins, and lipids or a mixture of them have entered to packaging industry. One of the proteins which is abundant and cheap in Iran and recently efforts have been made to find new applications for it is whey protein. Current study has investigated the effects of coating weight on the strength (tear and burst), barrier (air, oil and water permeability) and physical properties (coating weight) of whey protein coated light paper. In this study, two speeds of 30 and 50 mm/s were used for paper coating and the influence of the two different coating weight on paper’s properties was evaluated. Results show that the strength and barrier properties of coated papers were improved by increasing the coating speed due to decrease in coating weight. Furthermore, the application of whey protein concentrate- sucrose is suitable for coating the papers used for packing oily foods such as pizza and confectioneries.