粉单竹热水预抽提过程碳水化合物的变化规律

Changing Rules of Carbohydrates during Hot-Water Pre-extraction of Bambusa Chungii

本文以粉单竹为原料,在水解温度90-150℃、时间40-100min、液比1∶4-1∶7范围内研究了热水预抽提过程碳水化合物的变化规律。结果表明：当水解温度为150℃、保温时间为100min、液比为1∶4时,水解液中木糖的溶出率为0.471%、葡萄糖的溶出率为1.315%、阿拉伯糖的溶出率为0.224%、半乳糖的溶出率为0.150%、甘露糖的溶出率为0.023%。热水预抽提过程中粉单竹的半纤维素容易溶出,主要单糖是木糖,还有相当含量的葡萄糖、阿拉伯糖,其次是半乳糖和甘露糖。温度的变化是影响主要糖组分溶出率的主要因素,其中对葡萄糖的影响最大,极差达到0.956;而固液比对糖溶出率的影响最小,特别是甘露糖,极差只有0.002。因此在热水预抽提过程中应该严格控制预抽提温度,以达到在短时间、小液比内半纤维素溶出、减少纤维素降解的目的。

Changing rules of carbohydrates during hot- water pre- extraction of Bambusa Chungii under the conditions of temperature 90 - 150℃,reaction time 40 - 100 min and ratio of solid to liquid 1∶ 4 - 1∶ 7 were studied.The results showed that the dissolution rate of xylose was 0. 471%,glucose was 1. 315%,arabinose was 0. 224%,galactose and mannose were 0. 150% and 0. 023% under the conditions of temperature 150℃,reaction time100 min and ratio of solid to liquid 1∶ 4. Hemicellulose of Bambusa Chungii was dissolved easily. The main monosaccharide is xylose,glucose and arabinose are the second and only a small amount of galactose and mannose exists. The change of hydrolysis temperature is the main factor affecting on dissolution rate of carbohydrates,especially glucose by the differential range of 0. 956. However,the ratio of solid to liquid is minimum,the differential range of 0. 002 for mannose. Therefore,the pre- extraction temperature should be strictly controlled during hot- water pre- extraction process,in order to achieve the purpose of hemicellulose dissolution and reducing the cellulose degradation in a short time,smaller ratio of solid to liquid.