Optimization of enzymatic hydrolysis from patin (Pangasius spp.) frame waste

Abstract

The objective of this study is to study the combined effects of hydrolysis time. temperature, pH and ratio of enzyme to substrate on the degree of hydrolysis of Patin frames using Response Surface Methodology (RSM). Besides that, the proximate composition of patin frame and patin hydrolysate powder was determined as well. The effects of independent factors were described using a three-level factors Face Centered Central Composite design. A model equation was proposed with regard to effects of temperature, time (min), enzyme to substrate ratio (E/S) and pH on degree of hydrolysis of Patin hydrolysis. Proximate analyses revealed that Patin frames consisted of 63.20% moisture, 10.67% protein, 17 .94% fat and 4.04% fat. The freeze dried Patin frame hydrolysate powder contained 5.20% moisture, 64.31 % protein, 25.9% fat and 0.64% ash. The enzymatic hydrolysis had increased the protein content and reduced the fat and ash content significantly. The protein recovery in Patin frames hydrolysate was as high as 71.60%. The optimum value for temperature, hydrolysis time, E/S and pH were found to be 55°C, 163 minutes, 1.99% and 9.45, respectively. Regression of coefficients indicates that all linear forms, namely temperature, time, E/S ratio and pH plus one quadratic form, namely temperature2 were significant (P < 0.05). The model showed a good fit in experimental data because 94.98% of the variability within the range of values studied could be explained by it.