Elaboração e caracterização de “isinglass” de bexigas natatórias de peixes

• Autor(a) principal: Maia, Leina Maria Herculano
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFS
• Texto Completo: http://ri.ufs.br/jspui/handle/riufs/16626
• topic: Tecnologia de alimentos; Gelatina de peixe; Extração ácida; Gelatina de peixe; Caracterização reológica; Acid extraction; Fish gelatin; Rheological characterization; CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS

Isinglass is a gelatin derived from tropical fish swim bladders which is readily soluble in organic acids and has been used to clarify beverages. The present work was aimed at obtaining isinglasses from swim bladders of fish, white hake (Cynoscion leiarchus) and Catfish (Catfish catfish), make tax-chemical characterization (composition) and physical (weight, yield and color) of bladders and isinglasses and assess the rheological properties of isinglasses (gel strength and viscosity). The bladders were weighed, washed, immersed in 0.8 M NaCl for 10 minutes, washed again, cut and subjected to two treatments for each species. Bladders Catfish: T1BA) immersion in a solution of 0.5 M acetic acid and T2BV) Immersion in commercial alcohol vinegar, both at a ratio of 1:30 (g / ml). Bladders hake: T1PA) immersion in a solution of 0.5 M acetic acid T2PV) Immersion in commercial alcohol vinegar, both at a ratio of 1:50 (g / ml). For extraction of collagen, the bladders were immersed in these solutions and kept at 4 ° C for two days. Subsequently the material was filtered, thereby obtaining a collagen solution, which was heated for 2 hours at 55 ° C, was placed in plastic trays and cooled to gases, 55 ° C for formation of gelatin films. The yields were isinglasses 24.55% (T1BA), 24, 05% (T2BV), 39.26% (T1PA) and 34.90% (T2PV). Significant differences were observed only in treatments of White Hake. The protein contents of isinglasses ranged from 81.99% (T2BV) to 82.98% (T1PA) difference was observed for the treatments of white hake. The pH in all treatments were considered acids when compared with the literature, due to the extraction method. The isinglasses treatment with vinegar had lower values Bloom (T2BV - 68.07 and T2PV gf - gf 78.30) while the other showed average Bloom (T1BA - gf and T1PA 140.47 - 151.22 gf). The treatment of bladders with acetic acid showed a higher melting temperature, thus indicating a higher-quality gelatin, which was also observed for gel strength. The isinglasses T1BA, T2BV T2PV and showed lower viscosity than T1PA and all the samples before or gelation temperature of 10 ° C (gelling temperature).