Characteristics of Fish Protein Hydrolysate from Yellowstripe Scad (Selaroides leptolepis) Produced by a Local Microbial Protease

Fish protein hydrolysate (FPH) containing small protein or peptides and amino acids has a great attention related to the provision of high protein foods to overcome the problem of malnutrition. This research was purposed to prepare FPH from yellowstripe scad (Selaroides leptolepis) by using a local microbial protease from Bacillus subtilis BII-1. Hydrolysis process was done in a laboratory scale (500 g minced fish) at 55oC for 6 h. The liquid hydrolysate was then spray dried using whey protein and maltodextrin at a concentration of 20 and 30% for each filler. The treatment of whey protein powder produced FPHs with higher protein content (31.71-33.97% db) and slightly yellowish in color compared to maltodextrin (11.88-16.66% db). Their foaming capacity and stability were 20-100% and 15% in 5-10 min, respectively. However, FPHs prepared with maltodextrin had no foaming capacity. The hydrolysates from both treatments had low water and oil absorption with the value less than 3 mL/g hydrolysate. A trial on scaling up production using 30 kg fish, showed that optimization or adjustment should be carried out due to the high amount and high protein content of the residual products.