Influence of Protein Concentration on the Properties of Crayfish Protein Isolated Gels

Abstract

Crayfish protein, present in the wastes from crayfish processing, has been investigated as an ingredient of surimi-like gel products, which may be regarded as a renewable, available, and low-cost raw material. The aim of this study was to evaluate the influence of protein concentration on the gelation behaviour and gel properties of crayfish protein isolate-based systems. Gelation was performed by heating crayfish protein isolate dispersions at 90°C for 30 min. Then, gels were cooled at 4°C and the evolution of linear viscoelastic properties upon setting was analysed for 24 h. An increase in both linear viscoelasticity and water holding capacity was found as protein concentration increased, although an asymptotic evolution was found at the highest CFPI concentrations. Scanning electron microscopy revealed occurrence of an extended cross-linked network for crayfish protein isolate gels. These results suggest that crayfish protein can be properly used as a valuable ingredient in food gels, where protein concentration may be modulated to enhance gel strength.

Keywords:

• Crayfish protein
• Gelation
• Linear viscolesticity
• Water holding capacity
• SEM

ACKNOWLEDGMENTS

The authors acknowledge the financial support from the MEC (FPU grant). This work was also part of a research project No. AGL2007-65709 supported by the Spanish MCYT and FEDER and No. 10-TEP-6134 supported by the CICE (Andalousian Government, Spain).