Trout skin gelatin-based edible film development

Area of Science:

• Food Science
• Materials Science
• Biotechnology

Background:

• The fishing industry generates substantial waste, including fish skin.
• Fish skin is a potential source of valuable proteins like gelatin.
• Developing sustainable packaging materials from by-products is an area of growing interest.

Purpose of the Study:

• To develop edible biopolymer films from trout skin gelatin (TSG).
• To investigate the effects of thermal processing and glycerol concentration on film properties.
• To assess the potential of TSG films for food packaging applications.

Main Methods:

• Gelatin extraction from trout skin using thermal denaturation.
• Formulation of film-forming solutions with varying glycerol concentrations (9-23%).
• Thermal treatment of solutions (80-100°C for 30-60 min) to form films.
• Characterization of TSG and film properties (amino acid composition, mechanical, barrier, solubility, color).

Main Results:

• TSG is rich in methionine and aspartic acid.
• Optimal film formation required heating at 90°C for 30 min.
• Increased glycerol reduced film strength and water vapor barrier but enhanced stretchability.
• Increased heating time decreased film solubility.

Conclusions:

• Trout skin gelatin can be processed into stable edible biopolymer films.
• These films exhibit useful physical and moisture barrier properties.
• TSG films offer a sustainable packaging solution for low-to-intermediate water activity foods, reducing waste in the trout processing industry.