大麦麦芽非淀粉多糖的含量和分子质量与其协定麦汁过滤速度的关系

摘要

以17个大麦麦芽样品为研究对象,采用协定糖化法分析了麦汁中与麦芽过滤速度相关的指标.Pearson相关性分析表明,过滤速度与黏度极显著负相关,与总阿拉伯木聚糖含量显著负相关;黏度与总阿拉伯木聚糖含量极显著正相关,与麦汁中的总β-葡聚糖含量显著正相关.β-葡聚糖和阿拉伯木聚糖分别用75％饱和度的硫酸铵和80％的乙醇沉淀后,采用凝胶过滤色谱法进一步分析了分子量大于1 000 kDa、500 ～1 000 kDa、50～500 kDa及小于50 kDa的4个分子量段B-葡聚糖和阿拉伯木聚糖的含量,相关性分析结果表明,分子量大于50kDa的阿拉伯木聚糖含量与过滤速度极显著负相关,与黏度极显著正相关;分子量大于1 000 kDa的β-葡聚糖含量与黏度极显著正相关,与总p-葡聚糖含量和总阿拉伯木聚糖含量相比,显著性水平和相关系数均有较大提高,是造成协定麦汁黏度高和过滤速度慢的重要因素.%Several parameters associated with filtration rate of 17 barley malt samples were analyzed by Congress mash.Pearson correlation analysis showed that the filtration rate was significantly negatively correlated with viscosity and total arabinoxylan content.Viscosity was significantly positively correlated with total arabinoxylan content and total β-glucan content.After precipitation with 75％ saturated ammonium sulfate and 80％ ethanol respectively,solutions of β-glucan and arabinoxylan were injected to gel filtration chromatography column to analyze the contents of β-glucan and arabinoxylan with molecular weight greater than 1 000 kDa,500-1 000 kDa,50-500 kDa and less than 50 kDa.The results showed that,contents of arabinoxylan with molecular weight greater than 50 kDa were highly significantly negatively correlated with filtration rate and significantly positively correlated with viscosity.,Content of β-glucan with molecular weight greater than 1 000 kDa were highly significantly positively correlated with viscosity.Compared with the total β-glucan and total arabinoxylan,the level of significance and coefficients of above correlation were greatly improved,which were main contributors to the high viscosity and slow filtration rate.