Optimization of Gluten-Free Bread Formulation Using Whole Sorghum-Based Flour by Response Surface Methodology

Area of Science:

• Food Science
• Cereal Science
• Gluten-Free Technology

Background:

• Growing celiac disease and gluten sensitivities drive demand for gluten-free (GF) products.
• Whole sorghum (Sorghum bicolor) is a nutritious, naturally GF grain.
• Producing leavened GF products like bread is challenging due to the absence of gluten.

Purpose of the Study:

• To optimize whole sorghum-based GF bread formulation for specific loaf volume and crumb firmness.
• To evaluate the impact of ingredients like milk powder, egg white, yeast, sugar, psyllium husk, xanthan gum, and soy lecithin.
• To achieve desirable technological and sensory properties in sorghum GF bread.

Main Methods:

• Response surface methodology (RSM) was employed for optimization.
• Key formulation parameters were systematically varied.
• Specific loaf volume and crumb firmness were measured as response variables.
• Sensory evaluation assessed consumer acceptability.

Main Results:

• RSM models achieved R2 ≥ 80%, indicating good fit.
• Optimized formulation increased specific loaf volume from 1.7 to 2.8 cm³ g⁻¹.
• Crumb firmness decreased from 10.6 to 3.7 N in the optimized bread.
• Egg white, milk powder, and psyllium contributed to a gluten-like network, enhancing volume.
• Soy lecithin improved dough stability and moisture, leading to a softer crumb.

Conclusions:

• Optimal formulation of whole sorghum GF bread achieved significant improvements in volume and texture.
• The developed sorghum bread demonstrated good consumer acceptability for texture and flavor.
• This research supports sorghum as a promising ingredient for developing high-quality GF bread alternatives.