Viscoelasticity of cowpea starch gels

The mechanical behavior of cowpea starch gels (10%, w/v) at small and large deformations were investigated in comparison with acorn, corn, and potato starches in storage at 4 degrees C for seven days. The rapid viscograms of starch paste (7%, w/v) revealed that cowpea starch had a larger setback (1, 135 cP) than other starches (465-830 cP), although peak viscosity (1,723 cP ) and pasting temperature (76 degrees C) were between those of corn and pot ato starches. Texture profile analysis of cowpea starch gel showed exceptio nally higher values for hardness, gumminess, chewiness and initial modulus than other starch gels. Cowpea starch gel also exhibited higher G' and smal ler tan delta compared with other starch gels, regardless of the storage ti me. A creep test revealed that the cowpea starch gel could remain highly re sistant to stress, showing the least deformation among the tested starch ge ls during storage up to seven days. The overall results disclosed that cowp ea starch was capable of forming exceptionally strong and elastic gels with good storage stability.