响应面法优化玉米浸液蛋白提取工艺及单细胞蛋白发酵的研究

探索了用等电点法提取玉米浸液中蛋白质的方法，并利用提取粗蛋白后的上清液生产单细胞蛋白。利用单因素实验分析了pH、温度、时间对蛋白提取的影响，通过响应面法确定等电点提取蛋白的最佳工艺，并研究了用酿酒酵母、产朊假丝酵母发酵离心上清液生产单细胞蛋白的条件。结果表明:等电点法提取粗蛋白的优化条件为:pH7.6、提取温度26.4 ℃、提取时间20 min，提取率为77.5%。以提取粗蛋白后的上清液生产单细胞蛋白，产朊假丝酵母优于酿酒酵母，当上清液中干物质浓度为8%、pH为5.5时，产朊假丝酵母发酵得到的菌落数达到1.6×109 CFU/mL。

Study on Extraction Process of Corn Steep Liquor Protein by Response Surface Methodology and Single Cell Protein Fermentation

The method of extracting protein from corn steep liquor by isoelectric point method was studied. The supernatant after extracting crude protein was used to produce single cell protein. Single factor experiment was used to analyze the influence of pH, temperature and time on protein extraction. Response surface methodology was used to determine the optimal process of isoelectric point extraction of protein. The conditions for the production of single cell protein from the supernatant of Saccharomyces cerevisiae and Candida utilis were studied. The results showed that the optimum conditions for crude protein extraction by isoelectric point method were as follows: pH 7.6, extraction temperature 26.4 ℃ and extraction time 20 min. The extraction rate was 77.5%. The conditions for producing single cell protein from the supernatant after extracting crude protein were as follows: Candida utilis was better than Saccharomyces cerevisiae. When the dry matter concentration in the supernatant was 8% and pH was 5.5, the colony number obtained by Candida utilis fermentation reached 1.6×109 CFU/mL.