فخرالدین صالحی

The objective of this study was to investigate the effect of replacing of rice flour with different ratios (0, 10, 20, and 20% w/w) of pumpkin powder on the rheology of batter and textural characteristics of gluten free rice cake. A factorial experiment with a completely randomized design with three replications was used for data analysis. The use of pumpkin powder in rice cake formulations significantly improved rheology of batter and textural characteristics of the samples (p< 0.05). By increasing the replacement level of rice flour with pumpkin powder to 30%, viscosity (from 682.66 to 3518.44 cp), hardness (from 21.11 to 53.97 g), cohesiveness (from 0.83 to 0.94), and springiness (from 9.74 to 13.49 mm) of batter cake improved significantly, but the adhesiveness (3.15 mJ) of batter increased compared to control (1.08 mJ) (p <0.05). However, the incorporation of pumpkin powder in the sample formulations up to 30%, increased the hardness (from 456.17 to 800.11 g), cohesiveness (from 0.56 to 0.67), springiness (from 8.68 to 11.43 mm), and chewiness (from 2231 to 6148 g) of the final cakes. Addition of pumpkin powder (up to 30%) in gluten free rice cake formulation caused the significant increasing of the total color differences (ΔE), browning index, and saturation index (chroma) in the cakes compared to control and moreover, increased the hue angle to 90owhich indicated an increase in the yellowness of the samples containing higher the replacement level of rice flour with pumpkin powder.