从薯渣中提取果胶及最佳提取条件的研究

本研究以马铃薯渣为原料采用盐酸提取——乙醇沉淀法获得果胶，分析酸度、温度、时间及乙醇体积分数等在果胶提取和沉淀时的影响。做单因素（温度、pH值提取时间和乙醇体积比等）实验和正交实验，结果表明，果胶提取的方法为：80℃热水浸泡30min，充分洗涤后，用盐酸调节pH=2、0，90℃下浸泡1．5h；乙醇沉淀条件为，调节pH=3．5，并保持乙醇的体积分数达到60％以上。此种方法获得的果胶酯化度为70％～80％，为高甲氧基果胶。

In the study,potato pectin was prepared by hydrochloride acid exraction,followed by alcohol precipiation and investigate the effects of strength of the acid, temperature, time and the alcoholic concentration in extracting and precipitating. Experiments of 4 factors（temperature,pH, time of extraction and alcoholic concentration）and orthogonal test. The result shows the optimum condition for potato residues pectin production： The raw material was socked in hot water （80℃）for 30 minutes;after washing fully,it was soaked again for 1.5 hours in a pH of 2.0 HCI solution and temperature of 90℃. The ethanol precipitation was adopted under the conditions of a pH of 3.5 and the alcoholic concentration should over 60 %. The method of extraction pectin had a degree of estefification of 70 % - 80 %, it＇ s high ester pectin.