Investigation of the application potential of vacuum modification with the use of aquafaba powder in gluten-free cake production

In this thesis, the potential of using aquafaba as an egg replacer in gluten-free cake production due to its functional properties and the effect of vacuum modification on gluten-free cake in terms of quality parameters are examined. For this purpose, egg white powder (YBT), aquafaba (AqF) and 50 % aquafaba substituted (AqF/YBT) gluten-free cake batters are prepared and baked by conventional baking and vacuum modification. Water activity, color and emulsion activity index of egg white powder and aquafaba powder, and pH, water activity and textural properties of gluten-free batters substituted with aquafaba are examined. Baking loss, color, texture, XRD, DSC and SEM analyzes are performed on gluten-free cake samples baked by conventional baking and vacuum modification. The water activity and emulsion activity of aquafaba powder are found to be lower than egg white powder, and its color is darker. It is observed that the differences between the water activity and pH values of gluten-free cake batters are statistically insignificant (p>0.05). Partial and total replacement of egg white powder by aquafaba in the gluten-free batter formulation lead to have higher firmness, consistency, cohesiveness and viscosity index compared to egg white powder containing counterpart (p<0.05). While a softer gluten-free cake with similar elasticity values is obtained using aquafaba; no statistically significant change in textural properties is observed with conventional baking and vacuum modification. XRD analysis shows that the use of vacuum modification and aquafaba limited starch gelatinization in gluten-free cake compared to the conventional method. SEM analysis shows that aquafaba addition and vacuum modification cause to lose the compact structure of gluten-free cake. DSC thermograms demonstrate that the peaks observed with the use of aquafaba powder in the formulation does not differ, but the baking method causes a change in the peaks of starch gelatinization