Foam Protein Separation And Identification And The Study Of Silicone Applications In Beer

The foam stability and the non-biological stability on the quality of beer werestudied. Including the identification of the beer foam isolated protein, establishingcontent determination methodology, the impact of the silica gel on beer stability andmaking a simple performance evaluation for Silicones.Firstly, the proteins were extracted form the beer foam fluid, the raffinate and thebeer. Foam protein content, molecular weight, amino acid composition, etc. weremeasured. The experimental results show that foam protein content of the beer foamliquid significantly more than the beer and the foam residue. Protein electrophoreticpattern were two broadband of approximately40kDa and less than a18kDa,distribution was similar, and no significant differences; The content of protein aminoacid form beer foam was largest, while these proteins’ composition and the proportionof hydrophobic amino acids were same.Secondly, on the basis of the above theoretical research, the binding of the dyeCoomassie Blue G-250to protein was studied, The optimum conditions weredetermine, Under these conditions, constructed calibration curve was used for theestimation of beer samples bubble protein concentration. The results showed thatthere was a good linearity relation between the absorbency and the content of standardproteins in the range of20-125μg/mL, detection limit was1.07ug/mL, the method ishighly sensitive. beer samples had good repeatability (RSD value was less than5%),the content of beer foam protein was significantly related with the bubble holdingvalue, While soluble nitrogen, protein Longding B distinction were not. The method isvery simple and fast.Lastly, the silica gel adsorption properties of the protein in the beer were studied.By measuring the non-biological stability, foam stability and filtration performance ofbeer with different amounts of silica gel adsorption, as well as silica gel adsorptionand specificity tests, the results were obtained. The silica gel have a strong affinitywith active proteins to cause beer chill haze, improve the stability of the beer,maintain good adsorption properties, but also have a good filtering performance andhave not any adverse effects beer the foam stability. The test also made a comparedanalysis about different silica gel performance, to offer a reference for selecting theappropriate silicone to improve non-biological stability of beer.