Estimation of freezing storage time and quality changes in hake (Merluccius merluccius, L.) by low field NMR

The potential of low field NMR (LF NMR) as a fast monitoring technique to estimate the quality of hake (Merluccius merluccius) frozen stored at -10 °C for up to 6 months was evaluated. LF NMR clearly detected three populations of water: water strongly bound to macromolecules (T 2b), trapped water (T...

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Detalhes bibliográficos
Autores: Sánchez Alonso, Isabel, Martínez, Iciar, Sánchez-Valencia, J. R., Careche, Mercedes
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2012
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/62612
Acesso em linha:http://hdl.handle.net/10261/62612
Access Level:acceso abierto
Palavra-chave:Fish muscle
Fish quality
Merluccius merluccius
Freezing storage
ast methods
Low field NMR
Descrição
Resumo:The potential of low field NMR (LF NMR) as a fast monitoring technique to estimate the quality of hake (Merluccius merluccius) frozen stored at -10 °C for up to 6 months was evaluated. LF NMR clearly detected three populations of water: water strongly bound to macromolecules (T 2b), trapped water (T 21) and free water (T 22). As storage time increased, and concomitant with an increase in the T 22 and a decrease in the T 21 water populations, the water holding capacity (WHC) and apparent viscosity values decreased and the shear strength increased, reflecting the characteristic loss of juiciness and tougher texture developed by hake during frozen storage. Two mathematical models were constructed: a simple regression using the biexponential analysis of the relaxation times (T 21, T 22) and amplitudes (A 21, A 22) and a partial least square regression (PLS) of CONTIN analysis. Both models seemed suitable to estimate the quality of the product.