Quality characteristics of egg-reduced pound cakes following WPI and emulsifier incorporation

The effect of partial (50 wt%) or total liquid egg replacement by whey proteins in combination with emulsifiers, i.e. hydroxypropylmethylcellulose (HPMC) and sodium stearoyl-2-lactylate (SSL), on the quality of pound cakes was investigated. Cakes containing whey protein isolate (WPI) solutions of varying concentrations (i.e. 20, 17 and 14% w/v) were first prepared. Complete egg replacement by WPI led to the preparation of cake batter of increased specific gravity as well as to final cake products of inferior quality with regard to volume, texture and hardness increase upon storage, compared to the control. In the case of partial liquid egg replacement by WPI solutions, cakes with acceptable sensory and quality characteristics were obtained, which were further improved following the addition of emulsifiers. During a storage period of four days the egg-reduced cakes exhibited a significantly lower staling rate depending mainly on the concentration of WPI and the presence of emulsifiers. Finally, the analysis of cake microstructure confirmed the positive effect of the co-addition of whey proteins and emulsifiers in egg-reduced cakes. This work made it possible to develop an alternative, egg-reduced cake of satisfactory quality, by using a combination of whey proteins with two common baking additives.