【摘要】 以甜菜渣为原料，采用酸法萃取、乙醇沉淀工艺提取果胶．首先通过正交实验［Ｌ９（３４）］确定了影响果胶得率的因素依次为ｐＨ、萃取温度、萃取时间．在此基础上针对果胶的产量、质量、色泽等对各个提取步骤进行了系统的比较研究，筛选出最佳萃取条件为：ｐＨ１．５、温度８５℃、时间６～８ｈ．萃取前原料的处理条件为：８０℃热水浸泡３０ｍｉｎ，充分洗涤后，用盐酸调ｐＨ１．５，浸泡１４ｈ．萃取液的脱色条件为高岭土在５０℃搅拌脱色３０ｍｉｎ．乙醇沉淀条件ｐＨ在１．５～２．５范围，醇的体积分数为６８％．果胶分子量为７６０００，酯化度６０％～７５％，半乳糖醛酸含量６０％～７０％．除胶凝度尚需进一步讨论之外，其它质量指数均达到食用果胶的国家标准更多还原

【Abstract】 Pectin was extracted from the residues of sugarbeet by using an acid extraction and ethanol precipitation technique. Factors which affected the extraction gain rate of pectin determined by the methods of orthogonal test [L 9(3 4)] were found to be the temperature, pH, and the time of extraction. According to the amount, quality and colour of the extracted pactin, a systematic comparative study was carried out, and the optimal conditions for the extraction were ascertained: pH was 1 5, the best temperature 85℃ and the time interval 6～8 hours. The separative procedure for the extraction of raw materials was as follows: the raw material was soaked in hot water (80℃) for 30 minutes; after washing fully, it was soaked again for 14 hours in a pH of 1 5 HCl solution. Decolorization of extraction liquid was carried out and the ethanol precipitation was adopted under the conditions of a pH of 1.5 ～2.5 and the alcoholic concentration of 68%. The extracted pectin had a molecular weight of 76000, with a fat rate of 60%～75% and a galacturonic acid concentration of 60%～70%. Except the degree of gelation which needs further study, the other quality indices are all accorded with the government standards for the edible pectin.更多还原