Characterization of gelatins from Nile tilapia skins preserved by freezing and salting

After Nile tilapia skin was preserved using the methods of freezing and dry salting, characteristics of skin gelatin were evaluated with regard to yield, rheological features and physical and chemical properties. Preservation was performed after filleting, at which time skins were either frozen (-18...

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Detalles Bibliográficos
Autores: Bordignon, Adriana Cristina, Souza, Maria Luiza Rodrigues de, Gasparino, Eliane, Yajima, Edson Minoru, Visentainer, Jesuí Vergílio, Goes, Elenice Souza dos Reis
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Brasil
Institución:Universidade Estadual de Londrina (UEL)
Repositorio:Semina. Ciências Agrárias (Online)
Idioma:inglés
OAI Identifier:oai:ojs.pkp.sfu.ca:article/34835
Acceso en línea:https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/34835
Access Level:acceso abierto
Palabra clave:Gelatin from fish skin
Amino acid profile
Gel strength
Oreochromis niloticus.
Gelatina de pele de peixe
Perfil de aminoácidos
Força de gel
Descripción
Sumario:After Nile tilapia skin was preserved using the methods of freezing and dry salting, characteristics of skin gelatin were evaluated with regard to yield, rheological features and physical and chemical properties. Preservation was performed after filleting, at which time skins were either frozen (-18°C) for 7 days or salted (25°C) for 7 days. Although no differences (p > 0.05) were observed with respect to humidity, protein, lipid, ash and calcium levels, gelatin from salted skins had a higher concentration of iron relative to frozen skins. Further, twenty-three fatty acids were detected in salted skins compared with merely three found in skin derived gelatin. Of amino acids found, glycine, alanine, proline and arginine were the most abundant. Hydroxyproline abundance in salted and frozen skin gelatin were 8.76% and 8.71%, respectively. In addition, salted skin gelatins had a greater accumulation of saturated fatty acids and lower rates of monounsaturated fatty acids. Salted skin gelatin had the highest yield (18g × 100g-1), gel strength (200 g) and viscosity (19.02mPas) when compared to the yield (17g × 100g-1), gel strength (12.7g) and viscosity (9.16 mPas) of frozen skins. Results show that gelatin from dry salted skin had the best yield and also had relatively better rheological properties, more iron, and better coloration relative to gelatin obtained from frozen skins of Nile tilapia.