# Sustainable Biopolymer Films from Amazonian Tambatinga Fish Waste: Gelatin Extraction and Performance for Food Packaging Applications

## TL;DR

This paper explores using waste fish skin from Tambatinga to create sustainable biopolymer films for food packaging with good UV and moisture protection.

## Contribution

The study introduces a novel use of Amazonian Tambatinga fish skin waste to produce high-performance biopolymer films for sustainable packaging.

## Key findings

- Tambatinga gelatin films showed excellent UV-blocking and low water vapor permeability.
- Higher glycerol content improved flexibility but reduced tensile strength of the films.
- The gelatin extraction process yielded high proline and hydroxyproline contents, suitable for film formation.

## Abstract

Tambatinga (Colossoma macropomum × Piaractus brachypomus), a hybrid Amazonian fish recognized for its superior growth performance, represents a valuable and sustainable source of collagen-rich raw material. Due to its tropical origin, the species’ skin may contain higher levels of amino acids, which can enhance the functional and structural properties of gelatin derived from it. The valorization of fish processing residues for biopolymer production not only mitigates environmental impacts but also reinforces the principles of the circular economy within aquaculture systems. This study explores the development of biopolymer films from Tambatinga skin, an abundant by-product of Brazilian aquaculture. The skins were cleaned and subjected to a hot water–acid extraction process to obtain gelatin. The extracted gelatin exhibited high proline and hydroxyproline contents (12.47 and 9.84 g/100 g of amino acids, respectively) and a Bloom strength of 263.9 g, confirming its suitability for film formation. Films were prepared using 2 g of gelatin per 100 g of film-forming solution, with glycerol added at 10 and 20 g/100 g of gelatin. The resulting films were transparent, flexible, and showed uniform surfaces. Increasing the glycerol concentration reduced tensile strength (from 59.4 to 37.9 MPa) but improved elongation at break (from 116% to 159.1%) and modified the films’ thermal behavior. Moreover, Tambatinga gelatin films demonstrated excellent UV-blocking performance (below 300 nm) and lower water vapor permeability compared to other gelatin-based films reported in the literature. These findings highlight the potential of fish skin—typically regarded as industrial waste—as a renewable and high-value raw material for the production of sustainable biopolymers. This approach supports resource efficiency, waste reduction, and the broader goals of sustainable development and circular bioeconomy.