Malays. Appl. Biol. (2017) 46(3): 15–21
OPTIMISATION OF ENZYMATIC PROTEIN HYDROLYSIS OF
MUD CRAB (Scylla sp.) TO OBTAIN MAXIMUM ANTIOXIDANT
ACTIVITY USING RESPONSE SURFACE METHODOLOGY
ZALIHA HARUN1, AMIZA MAT AMIN1*, NORIZAH MHD SARBON1,
MOHAMAD KHAIRI MOHD ZAINOL1 and KAZI NAZIRA SHARMIN2
1School of Food Science and Technology, Universiti Malaysia Terengganu,
21030 Kuala Nerus, Terengganu, Malaysia
2Department of Applied Food Science and Nutrition, Faculty of Food Science and Technology,
Chittagong Veterinary and Animal Science University, Khulshi, Chittagong 4225, Bangladesh
*Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Accepted 10 August 2017, Published online 4 October 2017
ABSTRACT
This study reported optimisation of enzymatic hydrolysis of mud crab meat using Protamex® to obtain maximum antioxidant activity using Response Surface Methodology (RSM). Prior to optimisation, screening of commercial food grade proteinases was carried out using Alcalase®, Protamex®, Neutrase® and papain. Protamex® was observed to give the highest DPPH scavenging activity. The enzymatic hydrolysis conditions used in the optimisation study were temperature (45-65ºC), pH (5.5-7.5), hydrolysis time (1-4 hours) and enzyme to substrate (E/S) ratio (1-3% Protamex®). A face-centered Central Composite Design (CCD) was employed. It was found that the relationship between hydrolysis conditions and DPPH scavenging activity could be explained by a quadratic model. Optimum condition was found to be at 54ºC, pH 5.5, 1% Protamex® and 1 hour of hydrolysis time. Validation experiment shows that the experimental DPPH scavenging activity (82.39 ± 0.16%) was close to the predicted value (82.64%). The hydrolysate prepared at optimum condition contained 5.52% moisture, 74.81% crude protein, 13.13% ash, 6.26% carbohydrate and 0.28% crude fat with IC50 for DPPH scavenging activity of 3.48 ± 0.05 mg/mL. This study shows that RSM can be used to explain the relationship between enzymatic hydrolysis conditions of mud crab meat and its antioxidant activity.
Key words: Mud crab, Enzymatic hydrolysis, Response Surface Methodology (RSM), antioxidant activity
