During the last couple of years, biopolymers such as polysaccharides and proteins have been arousing scientists’ interest as raw materials for biodegradable and/or edible packaging. Packaging materials to be developed should have good mechanical and visual properties, to protect and to offer the packed product a presentable look. This work was aimed at characterization of the mechanical and optical properties of nile tilapia myofibrillar proteins-based biofilms, as a function of filmogenic solution (fs) [composition: ph (2 to 3), protein (cp = 0.5 to 2.0g/100g solution) and glycerol concentration (cg = 30 to 70g/100g protein)]. Force and percentage deformation at break were determined by a puncture test and the apparent opacity by spectrophotometry, at 22ºc and ambient relative humidity. Easy handling and transparent biofilms were obtained in these conditions. Force and percentage deformation at break presented opposite behaviors as a function of cg (ph = 2.5 and cp = 1.25g/100g solution): increasing it from 30 to 70% and causing a variation in force and percentage deformation at break between 6.67n and 2.94n and 2.71% and 7.5%, respectively. Glycerol concentration and ph had significant effect over force at break (p <0.05). None of the studied factors showed any significant influence on the percentage deformation of biofilms at break, neither on their apparent opacity.
edible films; mechanical properties; myofibrillar proteins; nile tilapia
