Active edible films of methylcellulose with extracts of green apple (Granny Smith) skin

Abstract

The aim a present study was developed methylcellulose (MC) active edible films with extracts of green apple skin, as model systems of edible coating. Active edible films were developed by incorporation of ethanolic extract of freeze-dried apple skin (EEFD) and aqueous extract of apple skin (AES) at 10, 20 and 25% (v/v) concentrations. Analysis of thermal, mechanical and functional properties was carried out. Results showed that incorporation of green apple skin extracts into MC films contribute to total phenolic content and antioxidant properties. Addition of green apple skin extracts generated shifts toward lower glass transition temperature values regarding MC films without extracts. A lower tensile strength and increased elongation at break in MC-AES films were observed. Mechanical properties of MC-EEFD films were less affected by the increase in extract concentration due to absence of the plasticizing effect of sugars present in AES. The methylcellulose films are important for actives edibles coatings with applications in the food industry.