Response Surface Optimization of Enzymatic Hydrolysis of Silver Sillago (Sillago sihama) with Low Bitter Taste

Abstract

Eleven different commercial enzymes were used in this study, the MEAP (mixed enzymes for animal proteolysis) exhibited high nitrogen recovery, high degree of hydrolysis, and low bitter taste. In addition, at any DH, MEAP hydrolysates showed weakly bitter value. Response surface methodology (RSM) was used to optimize the hydrolysis conditions and the model equations were proposed. NR= + 93.73 - 4.29X1 + 3.68X2 +1.61X3 + 0.21X1X2 + 0.85X1X3 - 0.60X2X3 - 6.06 X12 - 1.6X22 + 0.054X32; DH= + 18.53 - 2.56X1 + 2.36X2 + 1.29X3 + 0.43X1X2 - 1.87X1X3 + 0.84X2X3 - 3.22 X12 - 0.44X22 - 0.52X32, where X1, X2 and X3 are the coded variables for temperature, E/S and pH, respectively. NR and DH at optimum conditions (temperature 55°C, E/S 1.5 percent, pH 7.5) were 95.76 percent and 20.19 percent, respectively. SSPH had high solubility over a wide pH range. One percent and 10 percent SSPH showed the low viscosity and good fluidity. Compared with FAO/WHO suggested patterns for preschool child, the essential amino acid scores of SSPH were greater than 95, which exhibited high nutritional value.