Egg replacement in cake: comparison between rheological properties of egg white and canola proteins

Eggs are one of the main ingredients in cake batter, however in recent years there is a growing demand for egg replacement, due mainly to health problems, dietary preferences or religious beliefs of consumers. This study investigated the gelation properties of egg white and two types of canola proteins (Protein A and B), by rheological analysis, evaluating the influence of protein concentration and sugar addition, with the purpose to find a valid protein alternative to be used as egg replacer in cake. Results showed that the addition of sugar resulted in higher gelation temperatures and delay of this phenomenon for both egg white and canola proteins, on the contrary increasing the protein concentration the gelation temperature decreased. In addition, plant-based proteins produced gel with lower viscosity compared to egg white, displaying lower gelling abilities, especially Protein B. Rheological tests suggested that canola proteins are able to form weaker gels, with narrowest linear visco-elastic range (LVR), compared to egg white, indeed, in particular for Protein B, the gel network was destroyed with the application of low stress. Protein A seemed to have better performances compare to B, thus it could be taken into consideration as egg replacer in cakes, preferably coupling it with other gelling agents, such us hydrocolloids or another plant-based protein.