采用单因素法,考察了酸浓度、提取时间、浸泡时间、微波功率和料液比(麦糟质量与水的体积的比)对低聚木糖提取率的影响,并在此基础上用正交设计对低聚木糖的提取工艺进行优化.实验结果表明,微波辅助提取低聚木糖的优化工艺组合为磷酸浓度为0.8mol·L^-1,提取时间为25min,浸泡时间为0.5h,微波功率为440W,料液比为1:50.在此工艺条件下,低聚木糖的提取率为49.87%,平均聚合度为3.49.
In this paper, the method of single factor was applied to investigate the influence of acid concentration, time of mustard soaked in water, extracting time, output power of microwave and ratio of solid to liquid on the extracting yield of xylooligosaccharides from Brewery's spent grain and then the extracting technic was optimized by orthogonal experiment. The experiment results showed the optimal conditions were as follows: the acid concentration was 0.8 mol · L^-1 , the extracting time was 25 min, the time of mustard soaked in water was 0.5 h, the output power of microwave was 440 W and the ratio of solid to liquid was 1 : 50. The extracting yield of xylooligosaccharides under the optimal conditions was 49.87% and the average degree of polymerization was 3.49.