酸热絮凝法提取甘薯淀粉分离汁水中的蛋白质

甘薯淀粉加工过程产生大量的淀粉分离汁水，其中含有丰富的蛋白质。采用酸热絮凝法从甘薯淀粉分离汁水中提取蛋白质，通过单因素试验，选择pH、温度、离心时间和离心转速为变量，利用正交试验分析影响甘薯淀粉分离汁水蛋白质提取效果的因素主次和较佳工艺，采用集成装置进行工艺模拟试验，检验甘薯淀粉分离汁水蛋白质提取的效果，并分析技术和经济可行性。结果表明：在温度为100 ℃、pH为4.0、离心转速3 500 r/min和离心时间10 min条件下，甘薯淀粉分离汁水的TN和COD_Cr去除率分别达到76.79%和40.66%；集成装置的蛋白质回收率达到48.86%，回收的粗蛋白质粉的蛋白质含量（以干基计）为73.22%，满足动物饲料原料要求。此外，对于1个大中型甘薯淀粉企业，1 m³甘薯淀粉分离汁水通过回收蛋白质可以创造毛利润20.51元。

Tentative study on protein extraction from sweet potato starch processing water by acid-heat flocculation

In the process of sweet potato starch production, a large amount of starch processing water is produced, which contains a lot of protein. The protein extraction from sweet potato starch processing water by acid-heat flocculation was studied. Through the single factor experiment, pH, temperature, centrifugation time and centrifugation speed were selected as variables. The main factors and optimum conditions were studied through orthogonal experiments. While, the effect and technical and economic feasibility of extracting protein from sweet potato starch processing water were analyzed through process simulation test with an integrated device. The results showed that the removal rates of TN and CODCr of sweet potato starch processing water reached 76.79% and 40.66%, respectively, when the temperature was 100 ℃, pH was 4.0, the centrifugation speed was 3 500 r/min and the centrifugation time was 10 min. The process simulation test results of the integrated device showed that the sweet protein recovery rate reached 48.86%, and the protein content (dry basis) of the recovered crude protein powder was 73.22%, which met the requirements of animal feed raw materials. In addition, for a medium-sized or large-sized sweet potato starch enterprise, 1 m3 sweet potato starch processing water could create a gross profit of 20.51 yuan by recycling protein. The protein extraction from sweet potato starch processing water by acid-heat flocculation had both technical and economic feasibility, which had a good promotion prospect.