Whole‐grain sorghum, orange pomace, and whey blends as a novel gluten‐free pregelatinized ingredient: Assessment of physicochemical and pasting properties (sorghum‐based pregelatinized flour)

This study aimed to obtain gluten‐free pregelatinized composite flours. A central composite rotational design was employed to study the impact of variation of the amount of whole‐grain sorghum flour, the conditioning moisture in composite flour, and the temperature in the third zone of the extruder on the flour properties. Conditioning moisture was the parameter that most influenced peak viscosity, trough, final viscosity, and setback of flours. Pregelatinized composite flours with similar pasting properties to cross‐linked chemically modified sorghum starches were obtained. While the sorghum flour presented 83.6°C for pasting temperature, 489 cP for peak viscosity, and 1,329 cP for setback, the pregelatinized composite flours presented values between 69–74.4°C, 129–257 cP, and 108–311 cP, respectively. The variation of the process and formulation parameters resulted in the production of flours with well‐differentiated pasting properties that would meet specific technological features for application in various foodstuffs, and some optimizations for food applications were shown. Practical applications Broadly driven by consumers who voluntarily avoid or limit gluten in their diets, the demand for gluten‐free (GF) products continues strong in the foodservice and retail sectors. Besides, GF has become an expectation for consumers seeking “clean label” products. However, the formulation and the manufacture of baked goods without gluten results in considerable technological problems for both cereal technologists and bakers. Limited research has been performed on the heat treatment of whole‐grain sorghum flour. This study provides essential information about the technological characteristics of sorghum‐based pregelatinized flours, especially related to their pasting properties. The results show that using these flours will be a good alternative for replacing cross‐linked chemically modified sorghum starches. Besides, these flours are valuable to increase the diversity of sustainable products made with gluten‐free whole‐grain cereals, easily suiting a “clean label ingredients.”