Gelatin extracted from jundiá skin (Rhamdia quelen): An alternative to the discarded by-product

• Published in: Food research international 2022-11, Vol.161, p.111829-111829, Article 111829
• Main Authors: Giacomelli da Silva, Camila, Souza Rodrigues, Angela, Carolina Lima, Ana, de Oliveira Mello, Renius, Dal Pont Morisso, Fernando, Cristina Prestes Dornelles, Rosa, Hashime Kubota, Ernesto
• Format: Article
• Language: English
• Subjects: byproducts; calorimetry; Chemical composition; color; denaturation; electron microscopy; Electrophoresis; Fish residue; food research; Fourier transform infrared spectroscopy; gelatin; hydroxyproline; industry; molecular weight; polyacrylamide gel electrophoresis; Protein ingredient; raw materials; Rhamdia quelen; snow; Technological properties; temperature; Thermal characterization; viscosity
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2022.111829

[Display omitted] •Jundiá skin (JS) showed potential application in the extraction of gelatin.•The yield of gelatin from jundiá skin (GJS) was superior to other animal sources without the use of enzymatic methods.•GJS obtained a high content of proteins and hydroxyproline in the composition.•GJS compatible thermal stability with commercial bovine gelatin.•Smooth and fibrous microstructures that provide better technological properties. The production of gelatin from by-products of the fishing industry values ​​the discarded raw material and serves a part of the population that does not consume products originating from mammals. Therefore, the objective of the research was to use the jundiá skin (Rhamdia quelen) (JS) to obtain gelatin (GJS) and characterize this product, not yet studied until the present moment. Thus, the extraction process showed a yield of 7.3 % for JS and 18.2 % for GJS (in wet weight). Both JS and GJS presented, in their composition, high concentration of protein (26.3 and 88.1 %), low levels of fixed mineral residue (1.0 and 1.9 %), lipids (1.7 and 1.5 %) and hydroxyproline content (1.5 and 7.2 %), respectively. The GJS dispersion had a pH value of 4.7 and the color analysis indicated a snow effect with a white appearance. Fourier transform infrared spectroscopy (FTIR) showed amide bands commonly found in gelatin, gel electrophoresis (SDS-PAGE) showed high molecular weight bands, differential scanning calorimetry (DSC) revealed a denaturation temperature of 69.4 °C and scanning electron microscopy (SEM) showed a compact and non-porous structure. The emulsifying property was high when subjected to a temperature of 80 °C for 30 min, while the foaming capacity was significant at a concentration of 1 %. The highest dispersivity was observed at pH 2.0 and, in this condition, the viscosity was higher than that of other gelatin sources (25.5 cP). In view of the above, attention is drawn to the use of JS as a raw material for obtaining gelatin and for the various possibilities of application.