Optimizing extraction process of Fish Protein Concentrate from Katley fish (Copper mahseer) using response surface methodology

Fish Protein Concentrate (FPC) has evolved as a possible alternative to fulfil the growing worldwide demand for low-cost, animal-based protein. The Mahseer fish, specifically the Katley fish (Copper Mahseer, Neolissochilus hexagonolepis), has tremendous potential as a raw material for FPC preparation. The Katley fish, recognized as the state fish of Sikkim, found in the Teesta and Rangeet rivers, making it an important resource for this purpose. The present study aimed to optimize the preparation of FPC from Katley fish by focusing on moisture and fat removal, while improving its nutritional profile. The effect of three independent variables (temperature (°C), time duration (minutes), and solvent-to-fish flesh ratio (v/w)) on crude protein content, moisture content, fat content, and product yield were studied by employing Response surface methodology, particularly Central Composite Design (CCD). The optimum parameters for production of FPC production were found to be as 60 °C temperature, 30 min of processing time duration, and 2:1 (v/w) of solvent-to-fish flesh ratio. At optimum condition, the resulting FPC was found to have a 17.80 % product yield, 76.98 % crude protein content, 4.96 %, moisture content and 0.76 % crude fat content. Since the resulting FPC contains >67 % crude protein, and has no >0.80 % fat, it is categorised as type A FPC.