Desenvolvimento de filmes biopoliméricos comestíveis contendo quitosana obtida a partir de escamas de peixe (Oreochromis niloticus)

Abstract

Chitosan can be combined with other biopolymers, such as sodium alginate and curdlan gum, to form biopolymeric films with enhanced characteristics. The aim of this study was to develop and characterize edible biopolymeric films containing chitosan obtained from fish scales (Oreochromis niloticus) for future use as a packaging material for processed meats like salami and sausage. To form the films, 18 treatments were conducted using 0.8 g of chitosan combined with 1 g, 1.6 g, and 2 g of alginate and curdlan gum. The samples were characterized for color (CIELAB), opacity, tensile strength (TS), elongation, thickness, biodegradation in soil, water vapor permeability, water solubility, and fluorescence. The films showed slight differences in color, with the sodium alginate samples being more yellowish. In terms of TS, the AG2 sample was the most resistant, with a result of 7.85E-04 MPa. The AC1.6 sample exhibited the highest elongation at 25.56%. According to the calculated linear regression, it was observed that the biofilms would be completely degraded within one to two years, with results varying between 101 and 696 days. The addition of cross-linkers glutaraldehyde and calcium chloride to the alginate samples made them more permeable (138.896 g.mm.day-1.kPa-1.m-2) due to ionic bonding forces between the COO groups and Ca2+. This same interaction made them less soluble (38.19%) and promoted rapid gelation and shortening. All samples showed opacity above 40%, indicating better UV protection. This is confirmed by the fluorescence data, where all samples exhibited a peak in the 500 nm region, indicating that energy is absorbed in the UV light region.