Recovery of Proteins from Rohu Processing Waste Using pH Shift Method: Characterization of Isolates

ABSTRACT

Yield and physicochemical characteristics of protein isolates recovered from rohu processing waste by acid- and alkali-aided protein solubilization methods were studied. pH 2.0 from acidic side and pH 13.0 from alkaline side resulted in maximum protein solubility, whereas minimum solubility was observed at pH 5.5. Except for pH 13.0, theoretical protein recovery was more than the actual recovery after centrifugation. Maximum protein recovery after the first centrifugation cycle was observed for pH 2.0 and pH 13.0, and the maximum protein recovery during the second centrifugation cycle was observed at precipitation pH 5.5 in both acidic and alkaline methods. Acidic and alkaline methods resulted in a total process recovery of 31.81% ± 0.001% and 31.11% ± 0.01%, respectively. Isolates prepared by acidic method had more whiteness and high foaming capacity, whereas isolates prepared using alkaline methods had less whiteness, tough texture, and high foaming stability. No microbial counts were detected in any of the isolates. Acid and alkaline methods described in this study can be used for the recovery of proteins from rohu processing waste with good yields and functionality.

KEYWORDS:

• Acidic
• alkaline
• recovery
• isolates
• rohu
• waste

Acknowledgments

Authors express their sincere thanks to the Dean, College of Fisheries, GADVASU, and the Head, Department of Harvest and Post-Harvest Technology, College of Fisheries, GADVASU, for their constant support during the work period. Authors also thank Mr. Bhaskar Vemu, Ph.D. scholar, Department of Veterinary Pharmacology and Toxicology, for his technical support during the work.