UTILIZATION OF HAZELNUT SKIN AND HAZELNUT FLOUR IN GLUTEN-FREE CAKES: CORRELATION OF BATTER RHEOLOGY WITH CAKE QUALITY

The effects of rice flour substitution with hazelnut skin (HS), hazelnut flour (HF), and HS-HF blend (1:1, w/w) at percentages of 0%, 5%, 10%, 15% (w/w) on gluten-free cake batters were studied from a rheological standpoint. Replacement with 5% HS increased Power-Law consistency index (K), reduced specific gravity and resulted in the highest cake volume. Increasing levels of HS gradually increased specific gravity, water activity, and reduced tan, leading to cakes with lower volume, darker (lower L*) color, harder texture. HF addition increased tan (at >5%) and specific gravity, producing cakes with lower volume, but similar color and texture to those of control. HS-HF blend improved cake color and hardness compared to HS added alone. Strong correlations were found between G() slope and cake volume (r=0.9939 for added HS, r=-0.9408 for added HF), the exponent a and cake volume (r=0.9447 for added HS, r=-0.8668 for added HF).