Protein Hydrolysate from Waste of Catfish Fillet Processing for Snakehead Fish Feed Formulation

The negative impact of fish processing industry waste needs to be minimized, by processing it into valuable products, one of which is fish feed. The objectives of this research were to determine the optimum dose of crude extract of B. cereus RGL.1.1 enzyme in hydrolyzing protein from the waste of catfish (Pangasius hypophthalmus) fillet processing and to evaluate the effectiveness of using protein hydrolysate in snakehead fish (Channa striata) feed. There were four doses of enzyme treatment for protein hydrolysis designed in a completely randomized design, namely, 0, 4, 6, and 8% (v/w) with three repetitions. Furthermore, to assess the quality of protein hydrolysate, an analysis of soluble protein level, hydrolysis degree, amino acid content, fatty acid content, and digestibility was carried out. The percentage of protein hydrolysate applied in the feed formula was 0, 15, 30, and 45% (v/w), which was designed in a completely randomized design with three replications. Absolute weight growth, specific growth rate, protein efficiency ratio, feed efficiency, and snakehead fish survival were measured to evaluate the effects of the feed formula. Results showed that the crude extract of B. cereus RGL.1.1 enzymes at a concentration of 6% (v/w) enhanced the availability of soluble proteins, amino acids, fatty acids, and feed digestibility. Protein hydrolysate application in snakehead fish feed formula up to 45% (v/w) can improve the growth performance (8.03%), protein efficiency ratio (25.66%), and feed efficiency (23.41%).