Optimization of preparation of antioxidant peptides from flaxseed meal by response surface methodology

Defatted flax seed protein was used as raw material to produce antioxidant peptides. The optimal protease and the effects of substrate concentration,dosage of enzyme,temperature,pH and enzymolysis time on DPPH radical scavenging activity were evaluated by single factor experiment. The response surface methodology was used to optimize the enzymatic hydrolysis process based on the results of single factor experiment. The results showed that trypsin had the best effect,and the optimal enzymolysis conditions were substrate concentration of 2%,temperature of 37℃,enzymolysis time of 3.00 h,dosage of enzyme of 4000 U/g,and pH8.50. Under the optimal enzymolysis conditions,the scavenging rate of DPPH radical and superoxide anion radical scavenging rate of the hydrolysates(1 mg/mL)was(63.64%±0.023%)and(19.98%±0.098%),respectively. The ABTS free rate of the hydrolysates(0.5 mg/mL)was(88.11%±0.059%). The results showed that antioxidant peptides from flaxseed meal exhibited good antioxidant activity.