Extrusion of gelatin-based composite films: effects of processing temperature and pH of film forming solution on mechanical and barrier properties of manufactured films

• Main Authors: Zainal Abedin, Nur Hanani, O'Mahony, James A., Roos, Yrjo H., Oliveira, Pedro M., Kerry, Joe P.
• Format: Article
• Language: English
• Published: Elsevier 2014
• Online Access: http://psasir.upm.edu.my/id/eprint/13269/1/Extrusion%20of%20gelatin-based%20composite%20films%20effects%20of%20processing%20temperature%20and%20pH%20of%20film%20forming%20solution%20on%20mechanical%20and%20barrier%20properties%20of%20manufactured%20films.pdf; http://psasir.upm.edu.my/id/eprint/13269/

The composite films, gelatin incorporated with corn oil were manufactured using a twin-screw co-rotating extruder. The effect of extrusion temperature (90, 105, 120 and 130°C) and film forming pH values (5.7–8.7) on the mechanical and barrier properties of gelatin-based composite films were investigated. Increasing the temperature from 90 to 130°C improved (P < 0.05) the tensile strength (TS) of films. Increasing temperature to 120°C improved (P < 0.05) water vapour permeability (WVP) values of gelatin-based composite films; however, this was accompanied by a decrease (P < 0.05) in gas barrier properties. Additionally the use of film forming solutions possessing high pH values improved the mechanical properties of films and caused a decrease (P < 0.05) in oxygen permeability. Neither temperature nor pH had any significant effect on the seal strength for any of the gelatin-based composite films manufactured. Confocal laser scanning microscopy (CLSM) results showed a corresponding increase in the number of oil droplets when processing temperature increased.