Abstract
Traditionally, fish carcass is headed and gutted to prepare a skin-on fillet in surimi production. In this study, tail and/or belly of grass carp carcass were further cut off in the filleting step. Yield, composition, gelling properties and aroma profile of surimi as affected by filleting methods were investigated by SDS-PAGE, ELISA, SEM, magnetic resonance imaging (MRI) and electron nose. Cutting tail off increased surimi yield by 14.0%, whereas cutting belly off decreased it by 11.2%. Cutting tail or belly off significantly decreased fat content, but did not change protein content, ash content, cathepsin (B, H and L) contents, nor protein patterns. Both breaking force and whiteness of surimi gel significantly increased after cutting tail off. Cutting belly off slightly increased whiteness of surimi gel. The microstructure of all the surimi gels was compact and uniform, with fractal dimensions (Df) ranging from 2.81 to 2.85. As for the macrostructure, cutting tail off apparently improved the integrity of surimi gel while cutting belly off did not. Aroma profiles of the surimi prepared under different filleting methods could be clearly distinguished by linear discriminant analysis (LDA). Our results indicate that cutting tail off contribute positively to surimi production.