单宁酸与麦胶蛋白结合反应的研究

Study on the Complexation Interaction of Tannic Acid with Gliadin

以单宁酸和麦胶蛋白分别作为引起啤酒浑浊的敏感多酚和敏感蛋白的模型物质,用分光光度法对影响单宁酸与麦胶蛋白结合反应的因素进行了研究。发现,麦胶蛋白的浓度影响单宁酸与麦胶蛋白结合的方式,也影响二者的结合比例。反应温度越低、反应时间越长,单宁酸与麦胶蛋白结合反应越完全。在很低的pH值时,单宁酸与麦胶蛋白结合能力很差,在pH4.0附近,单宁酸与麦胶蛋白结合反应较完全。低乙醇浓度下,随着乙醇浓度的上升,单宁酸与麦胶蛋白结合反应程度有所下降,而在较高乙醇浓度下却随之增大。

The influencin g factors on the interaction of tannic acid(as a model substance of the haze-act ive polyphenol in beer)with gliadin(as a model sbustance of the haze-active p rotein in beer)were studied with a spectrometic method.It was found that the c on-centration influences the mode and the ratio of complexation of tannic acid with gliadin.The lower the temperature and the longer the time ,the more compl ete was the reaction.At low pH,the complexation was low;at about pH4.0, the complexation reaction was rel-atively complete.At low alcohol concentra t ion,the extent of complexation reaction decreased with the increase of alcohol concentration;whereas at high alcohol concentration it was the other way round .