Effect of the thermal treatment of the filmogenic solution on the mechanical properties, color and opacity of films based on muscle proteins of two varieties of Tilapia

Myofibrillar and sarcoplasmic proteins are capable of forming a continuous matrix. Therefore, muscle proteins of two varieties of Tilapia were used to study the effect of the thermal treatment of filmogenic solutions (FS) on the mechanical properties, color and opacity of its films as a function of the plasticizer concentration. The mechanical properties of the films were determined by puncture and tensile tests and the color and opacity by colorimetry. In general, the films based on FS treated at 65degreesC/30 min were more resistant and more rigid, than the films treated at 40degreesC/30 min. This behavior was more pronounced in the case of FS with 2 g proteins/100 g FS. The color and opacity were mainly affected by the protein concentration in FS. The FS with 2 g proteins/100 g FS produced films more colored and opaque than those made with 1 g proteins/100 g FS. (C) 2004 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.