Abstract:

The aim of this work was to develop an edible composite film based on Chinese longsnout catfish (Leiocassis longirostris Günther)
skin collagen and chitosan. Using an orthogonal array design, mechanical properties of the film were investigated as a function
of mass ratio of collagen to chitosan, plasticizer type and concentration, and heating temperature and time. The results showed
that mass ratio of collagen to chitosan had a greater effect on the tensile strength of composite films than heating temperature.
The elongation at break was significantly affected by plasticizer type and concentration but only marginally by heating time. The
optimal preparation conditions that provided the best mechanical properties were determined as 6:4, 20%, 70 ℃ and 30 min for
mass ratio of collagen to chitosan, glycerol concentration (relative to total solutes), heating temperature and time, respectively.
The surface of composite films under the optimized conditions was smooth and without any bubbles. The tensile strength was
(21.98 ± 0.33) MPa and the elongation at break was (127.35 ± 3.03)%.

Key words: collagen, chitosan, edible composite film, mechanical properties