Study on the separation and hydrophobic property of beer foaming proteins

摘要

Beer foaming proteins are the most important components to structure beer foam. This kind of proteins is of high molecular weight, and of strong hydrophobic nature. Using several brands of beer purchased from Chinese market as materials, through foaming tower beer was separated into foam liquid (FB) and the remnant after foaming (RB), which, together with the original beer (OB) were researched about the changes of protein surface hy-drophobicity, and the effects of this change on foam stability. Meanwhile fraction of beer pro-teins by hydrophobic interaction chromatography (HIC) was carried out. It was found that the molecular distributions have something to do with the surface hydrophobicity, and the a-mino acid compositions are the precondition of protein surface hydrophobicity. Hydrophobicity value Q calculated from ammo acid components showed the same changing trend basically as the surface hydrophobicity of proteins.