Towards healthier surimi: quality and nutritional benefits of flaxseed gum as a fat replacer in grass carp surimi gels

Abstract

This study evaluated the effects of replacing animal fat with flaxseed gum (FG) on the quality of grass carp surimi gels. Moderate FG substitution improved gel strength, elasticity, and texture. Low-field nuclear magnetic resonance analyses indicated that 60 % FG enhanced moisture distribution. Microstructure revealed denser, smoother networks in 60 % FG gels. Fourier Transform Infrared analysis showed increased β-sheet structures, indicating a more ordered protein network. Although high FG levels slightly reduced whiteness, overall appearance remained acceptable. Sensory evaluation identified 60 % FG as optimal for texture and flavor. In vitro digestion showed reduced early-stage protein digestibility due to the dense matrix and polysaccharide barrier, but final digestibility remained high across all groups. These results demonstrate that moderate FG substitution can enhance the structural, sensory, and nutritional properties of surimi gels, supporting its use as a natural fat replacer in developing healthier, low-fat surimi-based products.

Keywords: Digestibility; Fat substitution; Flaxseed gum; Surimi gel; Textural properties.