青稞酒糟中β-葡聚糖提取工艺优化及理化特性分析

Optimization of extraction process of β-glucan from highland barley vinasse and analysis of its physicochemical properties

中文关键词:  青稞酒糟  β-葡聚糖  提取工艺  分子量  傅里叶红外光谱，理化特性，流变特性

英文关键词:highland barley vinasse  β-glucan  extraction process  molecular weight  physicochemical properties  rheological properties

中文摘要:

      目的 探究青稞酒糟中β-葡聚糖提取工艺及其理化特性。方法 通过单因素和响应面实验优化确定β-葡聚糖提取工艺。利用傅里叶红外光谱(Fourier transform infrared spectroscopy, FT-IR)和高效排阻色谱-示差折光检测器-多角度激光光散射仪(high performance size exclusion chromatography-differential refraction detector-multi-angle laser light scatter, HPSEC-RID-MALLS)联用测定提取物中β-葡聚糖的结构和分子量, 并对其加工特性及流变特性进行分析。结果 青稞酒糟中β-葡聚糖最优提取条件为: 料液比为1:11 (m:V)、pH 8.5、提取温度80℃、搅拌速度600 r/min、提取时间3.0 h, 此条件下提取率为16.29%。FT-IR检测结果表明, 提取样品中具有β-葡聚糖特征吸收峰。多糖重均分子量为7.84×104 Da, 在100~140℃高温条件和中性偏碱性条件下稳定, 在碱性条件及低盐离子浓度条件下促进溶解。流变特性结果表明, β-葡聚糖水溶液表现出非牛顿流体的剪切稀化特性, 其表观黏度存在浓度依赖性, 具有固体弹性特性。结论 从青稞酒糟中提取的β-葡聚糖具有较好的加工特性及流变性, 为青稞酒糟的综合加工及增值化利用提供思路。

英文摘要:

      Objective To investigate the extraction process and physicochemical properties of β-glucan from the highland barley vinasse. Methods The extraction process of β-glucan was obtained by using single factor and response surface analysis. The structure and the molecular weight of β-glucan was determined by Fourier transform infrared spectroscopy (FT-IR) and high performance size exclusion chromatography-differential refraction detector-multi-angle laser light scatter (HPSEC-RID-MALLS). The processing characteristics and rheological properties of β-glucan were analyzed. Results By single factor and response surface analysis, the optimum extraction condition of β-glucan was as follows: The material liquid ratio of 1:11 (m:V), pH 8.5, extraction temperature of 80℃, stirring speed of 600 r/min, extraction time of 3.0 hours. Under this condition, the extraction rate was 16.29%. The FT-IR detection results indicated that the extracted sample had a characteristic absorption peak of β-glucan. The polysaccharide had weight-average molecular weight of 7.84×104 Da and was stable under high temperature conditions of 100–140℃ and neutral to alkaline conditions. It promoted dissolution under alkaline and low salt ion concentration conditions. The results of rheological properties indicated that the aqueous solutions of β-glucan possessed the shear thinning characteristics of non-newtonian fluids, its apparent viscosity was concentration-dependent and had solid elastic properties. Conclusion The β-glucan extracted from the highland barley vinasse has good processing characteristics and rheological properties. The results of the study can provide a reference for comprehensive processing and value-added utilization of highland barley vinasse.