棉籽粕脱酚废液中低聚糖的分离与回收研究

Separation and Recovery of Oligosaccharide in De-Gossypol Waste Liquid of Defatted Cottonseed Meal

在食用棉籽蛋白粉的制备过程中,常采用含水低碳醇溶剂进行脱酚,分离棉酚后的废液中含有丰富的低聚糖。试验所得棉籽粕脱酚废液呈深黄色,含可溶性总糖3.596 mg/mL,蛋白质0.923 mg/mL,可溶性固形物4.83 mg/mL。为将其中的棉籽低聚糖有效分离,分别对聚酰胺、D101树脂、中性氧化铝、硅胶和活性炭（AC）等5种常见吸附剂的脱色和吸附特性进行了分析。试验结果表明,5种吸附剂中,以AC的脱色和分离效果最佳。AC在快速脱色的同时,可吸附脱酚废液中大部分的蛋白质,对其中的低聚糖却吸附最少。在pH 3~5,AC用量3%条件下,室温（27℃）吸附30 min,可获得良好的脱色效果（脱色率95.54%）,同时将溶液中83.39%的蛋白质吸附,溶液中总糖的损失率仅为0.57%。

Low alcohol solvents are usually used to extract gossypol from cottonseed meal for preparing edible cottonseed protein flour.Gossypol was separated by deposition and the remained waste liquid contains plenty of oligosaccharide.Aiming at utilization of the oligosaccharide in the de-gossypol waste liquid,the decolour and adsorption effect of five kinds of adsorbent,i.e.,polyamide,D101 resin,neutral alumina,silica gel,and activated carbon（AC） to the de-gossypol waste liquid were investigated.The de-gossypol waste liquid used in the study was of deep yellow,and contained total sugar,protein and soluble solid substance 3.596,0.923,and 4.83 mg/mL,respectively.Results：AC is the most efficient one among the adsorbents tested.AC decolors the waste liquid quickly and at the same time adsorbs most of the protein in the waste liquid,whereas adsorbs little oligosaccharide.Under the conditions of AC dosage 3%,liquid pH 3~5,adsorbing for 30min at room temperature（27 ℃）,the decolor rate of de-gossypol waste liquid reaches 95.54%,the protein is adsorbed by 83.39%,and the total sugar only losses by 0.57%.