Fish skins are considered good sources to extract high quality gelatine for applications in the food industry, however, this fish gelatine may have a characteristic odor and taste, causing limitations for its application, especially as a food ingredient and in supplements. Several methodologies have been studied in order to remove or reduce the odor in products made with fish. Among these techniques, we can find degreasing and adsorption. The objective of this research was to deodorize the gelatine from the skin of yellow hake (Cynoscion acoupa) using three different methodologies: activated charcoal, ethanolic delipidation and their combination. Gelatin was obtained from the immersion of the skins in acidic and alkaline solutions. The desorization by delipidification occurred with the use of an ethanol solution (1:2) and the adsorption made use of activated charcoal in powder (0.5%) and in grain (0.7%). Analyzes were carried out to evaluate the physical-chemical, technological and sensorial quality of the gelatins. The analysis results were submitted to ANOVA and Tukey Test (p <0.05). All physicochemical parameters analyzed in the present study showed a significant difference between the studied variables, except for proteins, lipids and moisture. The variables of emulsifying capacity, gel strength, melting point showed a significant difference between the deodorization methodologies in relation to the control treatment. The EGAC treatment influenced the higher luminosity of the samples, presenting negative values in the a* parameter. The treatment with powdered activated charcoal influenced the lower chromaticity and lower yellowish tone. According to the electropheretic profile, samples E, ACP and EGAC showed collagen α and γ bands. From the FTIR analysis, the presence of activated carbon in the desorizations (ACP, GAC and EGAC) resulted in lower interactions with the amine group. In the sensorial evaluation, the samples deodorized with activated charcoal behaved similarly in the sensorial evaluation, highlighting the behavior of the EGAC sample.
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