VIEW ARTICLE DOI: 10.1094/ASBCJ-45-0027
Egg Albumen as a Source of Foam Polypeptide in Beer. Charles W. Bamforth and Roy Cope, Bass PLC, 137 High Street, Burton-on-Trent, Staffordshire, England DE14 1JZ. J. Am. Soc. Brew. Chem. 45:0027, 1987.
Egg white (albumen) can be used to improve the foam characteristics of beers. Hydrolysis increases the foam potential of albumen to a level considerably superior to that of beer polypeptides and commercial whipping proteins from soy beans and also removes any tendency to cause hazes in pasteurized beer. It appears, however, that unhydrolyzed albumen is able to improve beer head in ways additional to acting as a simple source of protein. Addition of hydrolyzed albumen can be used as a diagnostic test for poor foams through its effect on the head retention value of beers ultrafiltered to remove material of molecular size greater than 1,000. Hydrolyzed albumen has very little ability to protect beer foam from the deleterious effect of lipid, yet it does provide the polypeptide backbone to those beers that lack sufficient foam protein, for example, those of low original gravity, those encountering excessive degrees of proteolysis, and those incorporating high levels of sugar adjuncts. If a beer already contains sufficient foaming polypeptides, then its head will not be dramatically improved by hydrolyzed albumen. However, as no simple test exists for the quantitation of foaming polypeptides in beer, the inclusion of hydrolyzed albumen provides assurance that a beer will contain sufficient of these materials.
Keywords: Albumen, Hydrolysis, Foam parameters, Analysis of beer foam