Production and characteristics of sailfin catfish (Pterygoplichthys pardalis) protein hydrolysate

Abstract

Background: The sailfin catfish (Pterygoplichthys pardalis) is a freshwater fish from the Loricariidae family, and is considered an invasive species in Indonesia. The fish is usually neglected and discarded. Its protein hydrolysate is the product of the breakdown of proteins into amino acids through the hydrolysis of acids, bases, or enzymes. Therefore, this study aims to determine the hydrolysate characteristics of sailfin catfish (Pterygoplichthys pardalis) proteins, produced with different pH and hydrolysis durations. Methods: The hydrolysis was carried out with variable pH (control, 5, 7, 9) and hydrolysis durations (12 and 24 hours) in three replicates. Results: The hydrolysis duration, pH, and interaction of both variables had significant effects (p<0.05) on the parameters of yield, antioxidant activity, degree of hydrolysis, protein levels, and ash content. Similarly, the moisture content, hydrolysis duration, and pH were significantly affected (p<0.05), while their interactions were not (p>0.05). The pH treatment had a significant effect on fat content (p<0.05), while the hydrolysis length and the interaction between the two had no significant effect (p>0.05). Based on this study, the best resulting production of fish protein hydrolysate (FPH) from sailfin catfish were a for a combination of pH 9 and a hydrolysis duration of 24 hours. The characteristics of FPH produced were as follows: a yield of 57.39%, antioxidant activity 63.99%, degree of hydrolysis 40.67%, water content 7.28%, ash content 7.63%, fat content 5.10%, protein content 34.51%, molecular weight 6.14 -118.17 KDa, total essential amino acids 49.30%, and nonessential amino acids 50.71%. Conclusions: Two factors affected FPH characteristics in sailfin catfish (Pterygoplichthys pardalis). The best processing conditions to obtain optimal characteristics for FPH were a yield of 57.39%, antioxidant levels of 63.99%, a DH of 40.67%, a moisture content of 7.28%, ash content of 7.63%, fat content of 5.10%, and protein content of 34.51%.