本试验旨在探讨不同因素对高温脱脂豆粕蛋白提取率的影响。以高温脱脂豆粕为材料,传统的碱溶酸沉法与超声辅助手段相结合,通过单因素和正交试验设计,对影响其蛋白提取率的提取温度、水料比、pH、提取时间、粉碎细度、超声时间和超声功率等因素进行研究。结果表明,1)能显著提高蛋白提取率的各单因素条件分别是:粉碎细度≥40目,pH≥9,提取温度≥30 ℃,水料比≥20: 1 (mL/g),超声功率300~400 W,超声时间≥5 min。2)各因素对大豆蛋白提取率影响的次序为:提取时间>超声功率>水料比>超声时间>粉碎细度>提取温度>pH。由此可见,在一定范围内,蛋白提取率随着各因素设置水平的提高而提高;高温脱脂豆粕蛋白提取的最优条件组合为:提取时间45 min、超声功率500 W、水料比25: 1 (mL/g)、超声时间15 min、粉碎细度60目、提取温度45 ℃、pH 9.0。

This experiment was conducted to study the effects of different factors on protein extraction rate of high-temperature defatted soybean meal. Using the high-temperature defatted soybean meal as a raw material, soy protein was extracted by alkali-solution and acid-isolation assisted by ultrasound, and single factor and orthogonal experiments were performed to investigate the effects of extractive temperature, water to flour, pH, extractive time, crushing fineness, ultrasonic time and ultrasonic power on the extraction rate of soybean protein. The results showed as follows: 1) the condition which could significantly increase the protein extraction rate was: crushing fineness ≥ 40 mesh, pH ≥9; extractive temperature ≥ 30 ℃;water to flour ≥20: 1 (mL/g); ultrasonic power 300 to 400 W, ultrasonic time ≥5 min. 2) The factor which could affect the rate of protein extraction was: extractive time > ultrasonic power > water to flour > ultrasonic time > crushing fineness > extractive temperature > pH. It is concluded that within limits, with the increase of factor level, the protein extraction rate is improved. the optimal combination of Extraction conditions is: extractive time 45 min, ultrasonic power 500 W, water to flour 25: 1 (mL/g), ultrasonic time 15 min, crushing fineness 60 mesh, extractive temperature 45 ℃ and pH 9.0.