Produção e caracterização de gelatina a partir de subproduto do processamento do tambaqui Colossoma macropomum

Abstract

Fishing industries generate by-products and in recent years the expansion of fishing and aquaculture production processing has contributed to the growing amount of by-products in up to 70% of processed fish, represented by heads, viscera, skin, bones and scales. Technological alternatives in the use of this material are of great importance, as they contain valuable biological quality. Being a sustainable source of biocompounds with a high content of collagen, gelatins, enzymes, peptides and minerals. The skin with scales originating from the processing of tambaqui (Colossoma macropomum) stands out for its large volume and high resistance, making it an alternative source with potential for exploitation. Collagen can be extracted from this by-product and gelatine can be subsequently acquired by partial hydrolysis, which has stood out for having good characteristics such as wide availability and for having applicability in several areas, such as drugs, tissue engineering, food, beverage whitening, among others. In this sense, the first chapter of this work was a literature review on the international scientific platform Science Direct, which aimed to compile data regarding gelatin processing, extraction, yield and characterization, providing scientific theoretical basis for understanding the process, product developed and their application areas, where 67 works were found. It was possible to identify that 46% of the studies used by-products of freshwater species, and the most used species were tilapia and carp. 66% of the studies used a skin by product, highlighting the acid extraction method with 50%. Of the 67 works, 35 presented gelatin yield and it was possible to identify 18 analyzes for gelatin characterization, which highlighted gel strength, functional groups, morphology, molecular weight and turbidity. On the other hand, the second chapter aimed to perform the extraction and characterization of gelatin from the by-product (skin with scales) arising from the processing of tambaqui C. macropomum. The by-product underwent pre-treatment in solutions of Sodium Chloride (NaCl), Hydrochloric acid (HCl), Butyl alcohol, Sodium hydroxide (NaOH) and Acetic acid, followed by extraction of gelatin in distilled water . The average yield of the extracted gelatin was 4.77% ± 0.80 for each 100 g of processed by-product, the Fourier Transform Infrared analysis (FTIR), observed integrity and purity in the obtained biopolymer. The centesimal composition of gelatin determined for moisture 15.69%, crude protein 83.54%, lipids 0.17%, ash 0.22% and carbohydrates 0.38%. With pH values of 6.49 ± 0.73, gel strength of 236.22g ± 2.55 and viscosity of 7.51cP ± 0.65. It is concluded that studies have been developed in different segments for the extraction of gelatin, from by-products of different species of fish, being a potentially valid alternative to increase the added value of products within the production chain, avoid economic losses and reduce the impact environmental. Thus, the by-product skin with scales of tambaqui C. macropomum, which are often discarded, are presented as an alternative source for gelatine extraction, having excellent centesimal characteristics and pH, consistent with those of commercial gelatines, in addition to good rheological properties (viscosity and Bloom strength) as seen in the literature.