江苏单二啤酒大麦麦芽麦汁中混浊物质的研究

Identification of wort turbid substances in Jiangsu Daner Barley wort

对江苏单二啤酒大麦麦芽麦汁中混浊物质成分进行了研究,结果表明多糖是麦汁混浊的主要成分,含量为82.57%,其次为蛋白质和多酚。采用离子交换色谱技术对混浊物质中的糖类进行了研究,结果表明糖类物质的单糖组成以葡萄糖为主,其次为半乳糖、阿拉伯糖、木糖。采用SDS-PAGE电泳结合基质辅助激光解析飞行时间串联质谱（MALDI-TOF/TOF）对麦汁混浊物质中蛋白质组分进行了鉴定,结果表明蛋白质分子量主要分布于25~45ku及小于18.4ku的两个部分,且主要来自于麦芽水溶蛋白及醇溶蛋白,质谱分析表明混浊蛋白主要为AMY2/BASI复合体A链,此外还有少量的Z4蛋白、大麦醇溶蛋白γ3、油体钙蛋白2及BTI-CMe2.1。本研究结果对于改良江苏啤酒大麦及其麦芽品质具有指导借鉴意义。

Identification of wort turbid substances in Jiangsu Daner barley wort was performed.Results indicated that carbohydrates were the most abundant portion in wort turbid substances and the content of carbohydrates was 82.5%, followed by proteins and polyphenols.lon exchange chromatography was used to study the carbohydrates.It showed that the most abundant hydrolyzed monosaccharide was glucose,followed by galactose, arabinose and xylose.SDS-PAGE and MALDI-TOF/TOF were used to identify the protein components of wort turbid substances.Results revealed that the molecular weights of proteins were mainly 25 ~45ku and less than 18.4ku and most of these proteins were derived from water-soluble proteins and ethanol-soluble proteins of malt. Mass spectrometry analysis showed that the maximum amount of haze protein was chain A of AMY2/BASI complex,in addition to a small amount of protein Z4,γ3 hordein, caleosin 2 and BTI-CMe2.1.The results were instructive for the improvement of the quality of Jiangsu barley malt.