Egg White Foams in Sourdough Applications

February 10/Helsinki, Finland/Biotech Law Weekly -- "Egg white (EW) proteins are functional proteins, which possess certain biological activities (antimicrobial, antigenic and peptidase-inhibitory) that may influence the food processing or vice versa can be affected by processing," scientists writing in the Journal of Agricultural and Food Chemistry report.

"This study investigated the behavior of EW proteins within sourdough systems with respect to proteolysis and fermentation parameters, and the ability of EW to build foam structures with sourdoughs. Of the EW proteins, ovotransferrin was hydrolyzed in all sourdoughs (wheat, rye and germinated-rye), whereas the breakdown of ovalbumin was specific for germinated-rye sourdoughs, with the cysteine endopeptidases being responsible for the hydrolysis. The presence of EW in sourdough fermentations had no influence on the prolamin hydrolysis or the growth of starter culture, indicating that the peptidase-inhibitory and antimicrobial properties of EW play no important role in sourdoughs," wrote F. Erem and colleagues, University of Helsinki.

The researchers concluded, "EW foams, however, appeared as potential structure builders in sourdough applications and could serve as alternative structural agents in the production of baked goods with low gluten content."

Erem and colleagues published their study in the Journal of Agricultural and Food Chemistry ("Functional Characteristics of Egg White Proteins within Wheat, Rye and Germinated-Rye Sourdoughs." Journal of Agricultural and Food Chemistry, 2010;58(2):1263-1269).

Additional information can be obtained by contacting J. Loponen, University of Helsinki, Dept. of Food Technol, Agnes Sjobergin Katu 2, FI-00014 Helsinki, Finland.

From the February 15, 2010, Prepared Foods E-dition