Desenvolvimento e avaliação de filmes incorporados de extratos naturais e determinação da oxidação em filés de tilápia

• Autor(a) principal: Turella, Camila Cheker Brandão
• Data de Publicação: 2019
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/10274
• topic: Acetato de celulose; Antioxidantes; Extratos naturais; Pequi; Rosemary; Green tea; BHA; Pequi bark; Cellulose acetate; CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS

This study aimed to produce active biofilms with antioxidant action in the conservation of tilapia (Oreochromis niloticus) fillets. For this, by completely randomized design, natural extracts of pequi bark, araticum, cajazinho and saffron were extracted. All extracts were evaluated for phenolic compounds content and antioxidant capacity. The extract of pequi bark obtained the highest antioxidant capacity (1,874 μmol.g-1), and its phenolic profile showed that the main compounds responsible for its high antioxidant power were ellagic, gallic and protocatechic acids. Pequi bark, green tea / rosemary extracts and BHA were incorporated into cellulose acetate films. These films were analyzed for maximum supported stress, tensile strength, perforation strength, elongation, elasticity, CO2 permeability, migration of phenolic compounds in fat and water simulators and electron microscopy. Pequi bark extract films have good mechanical strength, with a rupture stress of 32.28MPa, a gradual and maximum migration of phenolic compounds to the simulating of two days, and also show to be porous and gas permeable. Films of four treatments (control, pequi bark, green tea / rosemary and BHA) were used to pack tilapia fillets, which were stored for 15 days at 4°C. The experiment was conducted in a randomized block design, consisting of four treatments and four replication. During the study period, the analysis of lipid (TBARS) and protein (carbonyl and sulfhydryl) oxidation were performed at times 0, 4, 7, 10, 12 and 15 days. At the end of this period, films with BHA and pequi bark extract were able to maintain the fillets with better oxidative rates, proving to be effective in preventing oxidation. Therefore, the extract produced from pequi bark showed potential antioxidant action and high effectiveness in combating oxidation, and can be used not only in fish but in various foods.