双酶法制备葵花籽肽的工艺研究

Two-step Enzymatic Hydrolysis for Preparation of Peptides from Sunflower (Helianthus annuus L.) Protein Isolates

利用双酶法水解葵花籽分离蛋白(SPI)制备葵花蛋白肽,探讨各因素对水解度(Degree of hydrolysis,DH)和肽含量的影响,目的在于确定葵花蛋白肽制备的最佳酶解条件。结果表明:最佳酶解条件为底物浓度5.0×10-2g/mL,温度为53.5℃,pH 8.5,按照[E/S]为1.0×10-2g/g加Alcalase 2.4 L,酶解104 min,调整pH为7.5,按照[E/S]为0.44×10-2g/g添加Flavourzyme酶解120 min。此工艺得到水解液中肽含量为4.25mg/mL,DH为30.97%,与单酶法相比,肽含量显著提高。

Two-step enzymatic hydrolysis reactions were investigated to prepare peptides t^om sunflower protein isolates. In order to maximize content of peptides and optimal degree of hydrolysis （DH）, crucial hydrolysis parameters were optimized. Results showed that the maximum content ofpeptides of 4.249 mg/mL was obtained under the following conditions in the first enzymatic step： Alcalase 2.4 Ldosage 1.0 ×10^-2g/g, hydrolysis time 104 min, temperaure 55℃, pH 8.5, and substrate concentration 5×10^-2 g/mL. In the second enzymatic step, the optimum conditions were,： Flavourzyme dosage 0.44×10^-2 g/g, reaction time 120 min and pH 7.5. Unde the optimum condition, the DH was 30.97%. In addition, much higher peptide contents than using single enzyme method was found when using this two-step enzymatic method.