超声强化制备大豆蛋白-乳糖接枝物工艺条件的优化

The Optimization of Soy Protein-lactose Conjugates Prepared by Ultrasonic Assistance

本文通过单因素结果并结合中心组合设计和相应面分析,研究了超声强化制备大豆分离蛋白(SPI)-乳糖接枝物的反应条件对接枝度的影响并得到了数学模型,优化了超声促进接枝反应的条件。结果表明:超声功率、超声时间和蛋白浓度对大豆蛋白-乳糖接枝物的接枝程度影响显著(P<0.05)。超声强化制备SPI-乳糖接枝物的最佳工艺条件为:超声功率250W,超声时间25 min,蛋白浓度为11 mg/mL,在此工艺条件下,接枝度最高可达到45.53%。结果表明:超声可以显著提高大豆蛋白-乳糖的接枝速率。

Optimization of graft reaction of soy protein and lactose by ultrasonic assistance was investigated using response surface methodology and central composite design after single factor. The influences of the variables of graft processes were studied and the regression equation of soy protein isolates -lactose conjugates prepared by ultrasonic assistance was established. Degree of graft was primarily affected by ultrasonic power, time and protein concentration. The optimum conditions were protein concentration （11 mg/mL）, ultrasonic power （250 W）, and ultrasonic time （25 min）. Comparing with traditional heating, ultrasonic assistance could shorten reaction time to 1/3. It suggested that ultrasonic assistance could accelerate graft reaction of soy protein isolates and lactose.