Effect of Balangu Seed Gum Addition on Rheological Characteristics of Batter and Qualitative Properties of Sponge Cake

Addition of hydrocolloid to cake formulation improved its sensory and textural properties. Balangu seed has remarkable amounts of gum with good functional properties and improved the rheological and textural properties. In this study, effect of Balangu seed gum addition at four levels 0, 0.5, 1 and 1.5 %, on batter rheology properties, and physical and sensory properties of sponge cake were studied. First the sponge cake batter containing different percentages of Balangu seed gum were prepared and their rheological properties using a Brookfield rotational viscometer were evaluated. Then physical characteristics of prepared cake include moisture and volume by standard methods, cake crumb color including L*, a* and b* values by image processing method, and sensory evaluation (total acceptance) by 9-point hedonic method were evaluated. Statistical analysis in completely randomized factorial design was studied and comparing the average at 5% level using Duncan's multiple range test was performed. With increasing Balangu seed gum in formulation of sponge cake, viscosity of batter increased. Sponge cakes batter were as non-newtonian fluids and pseudoplastic (shear-dependent) and thixotropic (time-dependent) type. With increasing the Balangu seed gum from 0 t 1.5 %, sponge cakes batters viscosity at shear rate of 20 s-1 ware increased from 12.84 to 32.80 Pa.s. The moisture content and volume of cakes were increased with increasing gum percentage. With increasing Balangu gum brightness of cakes increased due to increasing volume, as well as decreased yellowing of the samples. The L*, a* and b* indexes for sample containing 1.5 % gum were 88.67, -0.76 and 40.74, respectively. According to the sensory evaluation results, samples containing 1.5 % Balangu seed gum had the highest total acceptance score.