Optimization of the Effect of Different Concentrations of Xanthan, Guar and Carboxymethylmellulose Gum on Physicochemical, Rheological and Organoleptic Properties of Gluten-Free Biscuit Based on Rice Flour

Celiac disease is an autoimmune gastrointestinal disorder that occurs in sensitive individuals upon the consumption of gluten. It is one of the most common genetic abnormalities in the world, which is triggered during the process of digestion of gluten protein and the only way to treat it is to go on a gluten-free diet. The purpose of this research was to apply methods of Response Surface Methodology (RSM) and Central Composite Design (CCD), and to study the effect of independent variables including various concentrations of xanthan gum, guar and carboxymethyl cellulose gum (0, 0.3, and 0.6%) on physicochemical, rheological and organoleptic properties of gluten-free biscuits based on rice flour. The equations achieved through the examinations revealed that independent variables had significant effect (P < 0.05) on the parameters. Among the studied parameters, the effect of xanthan gum concentration was found as the most efficient variable. The results also showed that increasing the concentration of the gum would increase the moisture content, total ash, color changes, and overall acceptability of gluten-free biscuits, while decreasing their hardness and Spread Ratio. In general, the optimization of the researched variables showed that using 0.6% xanthan gum, 0.3% guar gum and 0.13% carboxymethyl cellulose gum would result in production of desirable sample products that would be similar in qualitative characteristics and overall acceptability to the wheat flour biscuits, and could be used for celiac patients’ diet programs.