Optimization of microencapsulation of α-amylase into beeswax by response surface methodology

In this work, α-amylase was encapsulated into beeswax and the effects of independent variables including beeswax content (1-3 g), enzyme concentration (0.78-1.82 mg/ml), Tween 20 level (0.5-1% (w/v), and stirring rate (800-1200 rpm) on the encapsulation efficiency of the encapsulated enzyme were optimized using response surface methodology (RSM). Beeswax content and enzyme concentration were significant parameters (p 0.05). Besides, the optimum conditions for the maximum encapsulation efficiency (40%) were 1 g beeswax, 1.82 mg/ml α-amylase, 1% (w/v) Tween 20 and 800 rpm stirring rate. Scanning electron microscopy (SEM) photos confirmed the size of encapsulated α-amylase between 3.98 to 69.53 μm. The catalytic efficiency of encapsulated enzyme (EE) was about 2 fold lower than that of free enzyme (FE). EE also showed higher thermal and storage stability than FE. These results suggested that this enzymatic treatment can be used in bakery industry.