Recovery and characterization of proteins from pangas (Pangasius pangasius) processing waste obtained through pH shift processing.

Study was conducted to recover proteins from pangas (Pangasius pangasius) processing waste (fillet frames) using pH shift method and to characterize the recovered isolates. pH 2.0 from acidic range and pH 13.0 from alkaline range were found to have maximum protein recovery (p < 0.05). During the recovery process, acidic pH (pH 2.0) was found to have minimal effect on proteins resulting in more stable isolates and strong protein gels. Alkaline pH (pH 13.0) caused protein denaturation resulting in less stable proteins and poor gel network. Both acidic and alkaline-aided processing caused significant (p < 0.05) reductions in total lipid, myoglobin, and pigment content thus by resulting in whiter protein isolates and gels. The content of total essential amino acids increased during pH shift processing, indicating the enrichment of essential amino acids. No microbial counts were detected in any of the isolates prepared using acid and alkaline extraction methods. pH shift processing was found to be promising in the utilization of fish processing waste for the recovery of functional proteins from pangas processing waste thus by reducing the supply demand gap as well pollution problems.