Pulses are naturally gluten free and therefore are an ideal ingredient in gluten free baking in addition to the nutrition, color, flavor and functionality improvement benefits. CODEX definition of gluten free is the products made only from ingredients that do not contain wheat (all triticum species, such as durum wheat, spelt and kamut), rye, barley, oats, or crossbred varieties which has been processed to reduce a gluten level not exceeding 20 ppm. The key for gluten free baking for yeast fermented products is to successfully replace the viscoelastic properties of gluten that provides structure and texture. Gelatinized starch and hydrocolloids are common ingredients to replace gluten functionality. Therefore, pre-gelatinized flour is preferred in gluten free baking over raw flour. Rice, corn and tapioca starch/flour are commonly used starch sources. However, these cereal grains tend to lack protein and fiber, which can be supplemented by additional pulse flour. Due to difference in the starch profile, especially amylose and amylopectin ratio, altered texture profile compared to the wheat is expected. Blending different starch sources or using baking aids such as emulsifier and enzymes can help improve the texture.
Addition of hydrocolloids and emulsifiers often improve gluten free bread formulation, providing gelling, thickening, water retention and texture improvement to the dough. Among different hydrocolloids, xanthan gum provides the best results on rheological tests when used in the gluten free bread formulated with a starch blend of rice flour, corn starch and sodium caseinate (Lazaridou et al. 2007). However, the baking quality of the bread with xanthan gum was lower than the other hydrocolloids such as CMC, pectin, agarose and β-glucan. As a final product quality, CMC and pectin resulted in the best quality as well as acceptability from sensory test (Lazaridou et al. 2007). Furthermore, Demirkesen et al. (2010) found using both emulsifier and hydrocolloid together produced the best result in terms of rheological properties and end product quality. As a result, blends of hydrocolloids with pulse flour may be needed in gluten-free application.